Rebreather Divers: A Field Guide
Any diver spending time in the company of the peculiar species known as Homo Tranquilisaqua, or “Rebreather Diver” will notice some minor differences between subspecies or breeds. All share the typical behaviors that trademark the species, such as a prideful strut and compulsive hoarding of bailout regulators like bowerbirds, as well as an urge to cluster together in loosely similar groups and exhibit passively territorial behaviors around different breeds.
But with a careful eye and a little bit of study it is easy to spot the subtle differences between them. Below you’ll find common sites you’ll find each of this odd creatures and some of the most common vocalizations.
______________________________
Hammerhead Diver (Extreme/Defender/XXR breed)
Most commonly found:
At the charging table with a handful of 18650s
Most likely to say:
“Can you deco from YOUR HUD?”
“I’m so glad they moved over to Shearwater…?” (Inflection of uncertainty common)
“Watch this!” -- removes cell tray.
Least likely to say:
“Whatever. A rebreather is a rebreather.”
“Who cares about the Deep Flooded Mine?!?”
“I really wish I’d gotten a Meg.”
Tell-tail markings:
Every component stamped “Made in Czech.”
Hammerhead Diver (Jurgensen breed)
Most commonly found:
Pacing on the phone with someone trying to figure out what’s going on
Most likely to say:
“Usually it doesn’t do this.”
“Does anyone have a gum-wrapper and a bobby pin?”
“At least I don’t have to open the head to turn it on.”
Least likely to say:
“Let’s go!”
“I’ve never missed a dive.”
“I wish the screen wasn’t so busy.”
Tell-tail markings:
LOTS of after-market Golem Gear components
Hollis Explorer Diver
Most commonly found:
At recreational dive shop demos
In the WTS listings on messageboards
Most likely to say:
“Want to buy my Explorer?”
“I knew I should have gotten a CCR.”
“Well… … at least it got me into it.”
Least likely to say:
“I love this thing!”
“You know what’s awesome? This has all of the disadvantages of CCR, but with none of the advantages!!”
“It travels so easily.”
Tell-tail markings:
Irresistable urge to hum John Williams’ “Imperial March”
Hollis Prism2 Diver
Most commonly found:
Bloody everywhere
Most likely to say:
“Would you pass me my stuff? It’s the M1 mask in the F1 fins and the DC1 bailout regs.”
“Look at this WOB chart.”
“Oops. I might have overpacked it a bit.”
Least likely to say:
“I really don’t like getting everything from one brand.”
“T-pieces would make waaaay more sense!”
“I had a REALLY hard time finding an instructor.”
Tell-tail markings:
The clear scrubber canister that, for some reason, NOBODY has had the good sense of putting a little rubber cockroach into the very bottom of under the moisture pad.
Inspiration Diver
Most commonly found:
Anywhere there aren’t any other options
Most likely to say:
“It’s the most popular unit on the market!”
“Fiber optics are the way of the future.”
“I can’t imagine diving without a temp stick.”
Least likely to say:
“I tried six different units before I decided on this.”
“Injection molding is so unreliable.”
“Of course I trust I packed my scrubber well!”
Tell-tail markings:
YELLOW!!!!!!!
Being humped by a turtle
JJ Diver
Most commonly found:
Somewhere terrifying
Most likely to say:
“You only really need 5lbs of sorb. Sure, for a 12 hour dive.”
“Yeah, the BOV was awesome, but you don’t really need it.”
“The stand is actually pretty useful!”
Least likely to say:
“OTCL have soooo much better WOB.”
“I just don’t know where to mount this bottle!”
“I wish this had a little more weight to it.”
Tell-tail markings:
Heavily scratched aluminum head-protector
KISS Classic Diver
Most commonly found:
In 2007
Shallower than 240 feet
Most likely to say:
"Manual is so much safer."
"All I need to fix any problem is five minutes in Home Depot."
"Take a look at some of these modifications..."
Least likely to say:
"It would be cool to fit a solenoid right here."
"It's so exciting how fast rebreather technology is moving!"
"Mounting the counterlungs is the fun part!"
Tell-tail markings:
A BOV deeper than a 1972 Cadillac Coupe Deville's dashboard
KISS Sidekick Diver
Most commonly found:
At Cave Adventures
Most likely to say:
“Of course you can sidemount off a boat!”
“It takes a little getting used to, and there are some positions you really can’t be in for long, and sometimes it does things you’re rather it didn’t, but the WOB is worth it for the simplicity.”
“Sidemount is NOT just a fad!”
Least likely to say:
“That guy Edd is an *******.”
“Thanks for recommending I learn CCR on backmount first.”
“Calibration is a snap!”
Tell-tail markings:
These will become harder and harder to spot in the wild as this breed passes through an incubation phase and become Sidewinder divers instead.
Liberty Diver
Most commonly found:
In various eastern European countries
Most likely to say:
Something in a language you can’t even identify
“They had to make the screen in 1 pica font to fit everything on there.”
“This can survive absolutely ANY failure! Except for the main bus. Then it has to be shipped back to Czech.”
Least likely to say:
“Can I borrow your tool kit? I need to get this thing apart.”
“There is such a thing as TOO MUCH redundancy.”
“I wish this wing had more lift.”
Tell-tail markings:
Little coats to keep the onboard tanks warm
Meg Diver
Most commonly found:
Among other Meg divers
On a quiet, black RIB on their way to an insertion point
Most likely to say:
“The lungs really aren’t that in the way… could you open my drysuit dump for me?”
“The loop isn’t backwards. YOUR loop is backwards!”
“Aren’t you ready yet?”
Least likely to say:
“I’ll have to skip this dive, I don’t know why my rebreather is doing this.”
“Isn’t black just so dreary?”
“I really wish I’d gotten a Hammerhead.”
Tell-tail markings:
ISC logo on EVERYTHING, including every valve, shirts, hats, and possibly underwear
O2ptima Diver
Most commonly found:
In north Florida
Most likely to say:
Nothing. It’s north Florida, Yankee.
Least likely to say:
“Chinese manufacturing is actually a lot more reliable these days.”
“These cartridges are so wasteful.”
“I can just never get service from those impersonal people at Dive Rite.”
Tell-tail markings:
Looks like quasimodo, moves like aquaman
Poseidon Cislunar Diver
Most commonly found:
Trying to figure out what error code 20-11 means
Most likely to say:
“It is NOT a toy!”
“Seriously… no it isn’t!”
“We’re about to have solid-state sensors, so PBBBLLTTT!”
Least likely to say:
“I wish the display was bigger.”
“You know what they say… they’ll just make a better idiot!!”
“I have no idea how much postage to Sweden is.”
Tell-tail markings:
PADI Course Director personalized license plates
Amphibious Outfitters t-shirt
RB80 Diver
Most commonly found:
Still on deco
Hanging around Extreme Exposure
Most likely to say:
"Electronics will kill you."
"Sure, it's heavy, complicated, and bulky as a 60s refrigerator... but at least it's safe."
"It's not a rebreather, it's a gas extender!!"
Least likely to say:
"I have WAY too many swagelok fittings!"
"I really have this tricked to suit me personally."
"I think I'm just going to bring this for a quick dip."
Tell-tail signs:
Red DUI Drysuit
Traveling in schools
rEvo Diver
Most commonly found:
Taking selfies
At the Add Helium booth
Most likely to say:
“The profile is soooo much smaller than yours. 1½ inches, at least!”
“I have four independent sets of electronics.”
“You just wear it on the plane like a really, really heavy metal backpack.”
Least likely to say:
“You only really need three cells.”
“Ugh! I just can’t stand gimmicks!”
“What’s CE?”
Tell-tail markings:
Custom, laser-cut cover-cover
6lbs weight anchored at the top of the unit
SF2 Diver
Most commonly found:
Making extremely snarky remarks
Most likely to say:
“It’s super easy to change back and forth from BM to SM.”
“Doesn’t matter that the counterlung is 4 feet from your chest, the WOB is great!”
“Yeahhhh… sometimes I do prefer my other rebreather.” (NOTE: They will only emit this vocalization if cornered.)
Least likely to say:
“Carbon fiber is so gaudy.”
“I’m sorry, I didn’t mean to offend you.”
“I’d rather be just commenting on a messageboard right now.”
Tell-tail markings:
Carbon fiber
Clever SF2 logo that looks exactly like “SF2”
______________________________
While this guide is by no means comprehensive I should hope that it will act as a primer for the next time you are at the dive site, having trouble identifying the subtle differences between rebreather divers. There are numerous lesser-known breeds which exhibit their own little quirks and may be worthwhile to research in more detail after sighting such a rare specimen.
Rebreather divers are an eccentric species which you may enjoy many hours observing the behaviors of in their natural habitat. Good luck and happy hunting.
Any diver spending time in the company of the peculiar species known as Homo Tranquilisaqua, or “Rebreather Diver” will notice some minor differences between subspecies or breeds. All share the typical behaviors that trademark the species, such as a prideful strut and compulsive hoarding of bailout regulators like bowerbirds, as well as an urge to cluster together in loosely similar groups and exhibit passively territorial behaviors around different breeds.
But with a careful eye and a little bit of study it is easy to spot the subtle differences between them. Below you’ll find common sites you’ll find each of this odd creatures and some of the most common vocalizations.
______________________________
Hammerhead Diver (Extreme/Defender/XXR breed)
Most commonly found:
At the charging table with a handful of 18650s
Most likely to say:
“Can you deco from YOUR HUD?”
“I’m so glad they moved over to Shearwater…?” (Inflection of uncertainty common)
“Watch this!” -- removes cell tray.
Least likely to say:
“Whatever. A rebreather is a rebreather.”
“Who cares about the Deep Flooded Mine?!?”
“I really wish I’d gotten a Meg.”
Tell-tail markings:
Every component stamped “Made in Czech.”
Hammerhead Diver (Jurgensen breed)
Most commonly found:
Pacing on the phone with someone trying to figure out what’s going on
Most likely to say:
“Usually it doesn’t do this.”
“Does anyone have a gum-wrapper and a bobby pin?”
“At least I don’t have to open the head to turn it on.”
Least likely to say:
“Let’s go!”
“I’ve never missed a dive.”
“I wish the screen wasn’t so busy.”
Tell-tail markings:
LOTS of after-market Golem Gear components
Hollis Explorer Diver
Most commonly found:
At recreational dive shop demos
In the WTS listings on messageboards
Most likely to say:
“Want to buy my Explorer?”
“I knew I should have gotten a CCR.”
“Well… … at least it got me into it.”
Least likely to say:
“I love this thing!”
“You know what’s awesome? This has all of the disadvantages of CCR, but with none of the advantages!!”
“It travels so easily.”
Tell-tail markings:
Irresistable urge to hum John Williams’ “Imperial March”
Hollis Prism2 Diver
Most commonly found:
Bloody everywhere
Most likely to say:
“Would you pass me my stuff? It’s the M1 mask in the F1 fins and the DC1 bailout regs.”
“Look at this WOB chart.”
“Oops. I might have overpacked it a bit.”
Least likely to say:
“I really don’t like getting everything from one brand.”
“T-pieces would make waaaay more sense!”
“I had a REALLY hard time finding an instructor.”
Tell-tail markings:
The clear scrubber canister that, for some reason, NOBODY has had the good sense of putting a little rubber cockroach into the very bottom of under the moisture pad.
Inspiration Diver
Most commonly found:
Anywhere there aren’t any other options
Most likely to say:
“It’s the most popular unit on the market!”
“Fiber optics are the way of the future.”
“I can’t imagine diving without a temp stick.”
Least likely to say:
“I tried six different units before I decided on this.”
“Injection molding is so unreliable.”
“Of course I trust I packed my scrubber well!”
Tell-tail markings:
YELLOW!!!!!!!
Being humped by a turtle
JJ Diver
Most commonly found:
Somewhere terrifying
Most likely to say:
“You only really need 5lbs of sorb. Sure, for a 12 hour dive.”
“Yeah, the BOV was awesome, but you don’t really need it.”
“The stand is actually pretty useful!”
Least likely to say:
“OTCL have soooo much better WOB.”
“I just don’t know where to mount this bottle!”
“I wish this had a little more weight to it.”
Tell-tail markings:
Heavily scratched aluminum head-protector
KISS Classic Diver
Most commonly found:
In 2007
Shallower than 240 feet
Most likely to say:
"Manual is so much safer."
"All I need to fix any problem is five minutes in Home Depot."
"Take a look at some of these modifications..."
Least likely to say:
"It would be cool to fit a solenoid right here."
"It's so exciting how fast rebreather technology is moving!"
"Mounting the counterlungs is the fun part!"
Tell-tail markings:
A BOV deeper than a 1972 Cadillac Coupe Deville's dashboard
KISS Sidekick Diver
Most commonly found:
At Cave Adventures
Most likely to say:
“Of course you can sidemount off a boat!”
“It takes a little getting used to, and there are some positions you really can’t be in for long, and sometimes it does things you’re rather it didn’t, but the WOB is worth it for the simplicity.”
“Sidemount is NOT just a fad!”
Least likely to say:
“That guy Edd is an *******.”
“Thanks for recommending I learn CCR on backmount first.”
“Calibration is a snap!”
Tell-tail markings:
These will become harder and harder to spot in the wild as this breed passes through an incubation phase and become Sidewinder divers instead.
Liberty Diver
Most commonly found:
In various eastern European countries
Most likely to say:
Something in a language you can’t even identify
“They had to make the screen in 1 pica font to fit everything on there.”
“This can survive absolutely ANY failure! Except for the main bus. Then it has to be shipped back to Czech.”
Least likely to say:
“Can I borrow your tool kit? I need to get this thing apart.”
“There is such a thing as TOO MUCH redundancy.”
“I wish this wing had more lift.”
Tell-tail markings:
Little coats to keep the onboard tanks warm
Meg Diver
Most commonly found:
Among other Meg divers
On a quiet, black RIB on their way to an insertion point
Most likely to say:
“The lungs really aren’t that in the way… could you open my drysuit dump for me?”
“The loop isn’t backwards. YOUR loop is backwards!”
“Aren’t you ready yet?”
Least likely to say:
“I’ll have to skip this dive, I don’t know why my rebreather is doing this.”
“Isn’t black just so dreary?”
“I really wish I’d gotten a Hammerhead.”
Tell-tail markings:
ISC logo on EVERYTHING, including every valve, shirts, hats, and possibly underwear
O2ptima Diver
Most commonly found:
In north Florida
Most likely to say:
Nothing. It’s north Florida, Yankee.
Least likely to say:
“Chinese manufacturing is actually a lot more reliable these days.”
“These cartridges are so wasteful.”
“I can just never get service from those impersonal people at Dive Rite.”
Tell-tail markings:
Looks like quasimodo, moves like aquaman
Poseidon Cislunar Diver
Most commonly found:
Trying to figure out what error code 20-11 means
Most likely to say:
“It is NOT a toy!”
“Seriously… no it isn’t!”
“We’re about to have solid-state sensors, so PBBBLLTTT!”
Least likely to say:
“I wish the display was bigger.”
“You know what they say… they’ll just make a better idiot!!”
“I have no idea how much postage to Sweden is.”
Tell-tail markings:
PADI Course Director personalized license plates
Amphibious Outfitters t-shirt
RB80 Diver
Most commonly found:
Still on deco
Hanging around Extreme Exposure
Most likely to say:
"Electronics will kill you."
"Sure, it's heavy, complicated, and bulky as a 60s refrigerator... but at least it's safe."
"It's not a rebreather, it's a gas extender!!"
Least likely to say:
"I have WAY too many swagelok fittings!"
"I really have this tricked to suit me personally."
"I think I'm just going to bring this for a quick dip."
Tell-tail signs:
Red DUI Drysuit
Traveling in schools
rEvo Diver
Most commonly found:
Taking selfies
At the Add Helium booth
Most likely to say:
“The profile is soooo much smaller than yours. 1½ inches, at least!”
“I have four independent sets of electronics.”
“You just wear it on the plane like a really, really heavy metal backpack.”
Least likely to say:
“You only really need three cells.”
“Ugh! I just can’t stand gimmicks!”
“What’s CE?”
Tell-tail markings:
Custom, laser-cut cover-cover
6lbs weight anchored at the top of the unit
SF2 Diver
Most commonly found:
Making extremely snarky remarks
Most likely to say:
“It’s super easy to change back and forth from BM to SM.”
“Doesn’t matter that the counterlung is 4 feet from your chest, the WOB is great!”
“Yeahhhh… sometimes I do prefer my other rebreather.” (NOTE: They will only emit this vocalization if cornered.)
Least likely to say:
“Carbon fiber is so gaudy.”
“I’m sorry, I didn’t mean to offend you.”
“I’d rather be just commenting on a messageboard right now.”
Tell-tail markings:
Carbon fiber
Clever SF2 logo that looks exactly like “SF2”
______________________________
While this guide is by no means comprehensive I should hope that it will act as a primer for the next time you are at the dive site, having trouble identifying the subtle differences between rebreather divers. There are numerous lesser-known breeds which exhibit their own little quirks and may be worthwhile to research in more detail after sighting such a rare specimen.
Rebreather divers are an eccentric species which you may enjoy many hours observing the behaviors of in their natural habitat. Good luck and happy hunting.
