Waterproof Key Bag for Diving

[Marlene996]

I hope this is in the right place and if not please let me know where to move it!

A little over a year ago I started making a simple new product for surfers to put their car key in and take in the water (instead of hiding in the sand or somewhere equally as sketchy). At Surf Expo last September I had a lot of interest from Dive shops in Florida and the Virgin Islands expressing frustration with the tube shaped products failing and looking for an alternative. Until then I had not considered it for divers as I was diving from a boat and didn't need to take my key.

Since then we have sent The Surf Bag on repeated dives between 12 and 30 meters and have had no failures. If you are familiar with Kewalos Harbor and the Sea Tiger wreck just off Waikiki, this area was our playground.

The Surf Bag (patent pending) is a small waterproof pocket made from retired airline life vests. It has a marine grade steel grommet at one end and uses a TruZip locking zip. It was designed to fit flat the pocket of most if not all board shorts, so it will easily hold a credit card, ID card, paper fishing license, and large electronic key FOB. A Disclaimer for diving use: It is not recommended at this time to use this bag to take your button activated electronic key FOB diving. Although The Surf Bag will keep your key and other goods dry, it is unclear what the effect is of multiple atmospheres on the activating buttons potentially engaging the battery at this time.

A bit of history on the material, life vests are stored in air tight plastic under your seat on the airplane for 5-10 years. What expires on these is the inflater canister and the chemical that activates the shoulder light when wet. It is cheaper to buy a whole new life vest than replaced these two components so the vests were disposed of... until now!

I designed The Surf Bag in Hawaii and it is manufactured in California (and soon also Washington State).

Now that I am confident that this product can is secure enough for scuba diving (to 30m) I'm ready to promote it in the dive world, starting here. I've also become a proud Scuba Board Sponsor as of today!

If you would like to learn more about my product, please ask questions here or visit my website: www.thesurfbag.com
If you would like to buy one please use this discount code for 15% off: ScubaBoard15

If you are in Hawaii, you can also find The Surf Bag at Abundant Life Natural Foods in Hilo and HIC in Kona, HIC on Maui, and on Oahu in HIC, Downing Surf, Wikiki Sand Bar in the Waikiki Beach Marriot and other locations you can see on our website.

I'd really love any questions, tips, feedback etc!
Also if you are on Oahu in April and would be interested in making videos and photos of the bag while diving please DM me. They found my PFO a year ago and I am still stuck waiting for approval for my closure.

 

[tursiops]

A flexible bag does NOT prevent pressure on what is inside; it only keeps the contents dry.
Some electronic devices are harmed (or perhaps just turned on and thus the batteries run down) by pressure...not just by water.
You might want to be clearer about this in your advertising. Maybe not so good for scuba divers.

 

[lexvil]

It does look like a great idea for it’s original purpose os surfing. Pressure can be an issue for modern fobs though so for scuba divers you may need to rethink it as is.

 

[rhwestfall]

I like it!

A great place for a [chipped] key, cash, cards, license...

I'm not needing the rigid case, so this fits the bill for me (no pun intended)!

 

[tursiops]

I like it!

A great place for a key, cash, cards, license...

I'm not needing the rigid case, so this fits the bill for me (no pun intended)!

Yep, if all you need is to keep things dry, it might be as good as or even better than other flexible bag solutions. But probably only the key might need to be kept dry...

 

[lowwall]

A flexible bag does NOT prevent pressure on what is inside; it only keeps the contents dry.
Some electronic devices are harmed (or perhaps just turned on and thus the batteries run down) by pressure...not just by water.
You might want to be clearer about this in your advertising. Maybe not so good for scuba divers.

Exactly. You would not want to use this for any key that contains a battery. All the buttons will likely get continuously pressed at depth. At best this will deplete the battery extremely quickly. At worst it could cause local heating which could damage the key or melt a hole in the bag.

@Marlene996, if you intend to sell this to divers, you should have a warning that it is not to be used for key fobs with batteries when diving. Traditional or chip keys without buttons should be fine.

 

[Marlene996]

This is great feedback.

@tursiops @lowwall

We have had some discussion on this. We are using the key fob from my 2024 Honda minivan to 15 meters and this is not enough pressure to engage the buttons. I will do some research to find out what actually pressure engages the key fob buttons. The battery is an excellent point, if it would be at risk for overheating due to pressure on the battery alone. This is something that hadn't yet occurred to me and also why this forum is so great. I will do more research on this before advertising it safe for electronic fobs with batteries.

As for soft verse hard at depth, of course the soft doesn't stop the pressure but the flexibility of the soft bag and the zip allow pressure to effect the material and air inside without forcing failure (cracking or breaking as a result of air internally shrinking). To my understanding with the plastic tubes this has resulted in cracking and with metal tubes the pressure on the seal can result in a failure gap between the seal and the metal if not properly looked after like all your other seals on your dive equipment. Of course the zip on The Surf Bag should also be taken care of but I fully believe it is of better quality and durability that the o-rings on the tubes if pressure isn't going to be a problem for the battery.

 

[grantmac]

I imagine a 3d printer guard could be put over the fob to prevent pressure. Much like what is used in the Divevolk phone housing.

 

[lowwall]

This is great feedback.

@tursiops @lowwall

We have had some discussion on this. We are using the key fob from my 2024 Honda minivan to 15 meters and this is not enough pressure to engage the buttons. I will do some research to find out what actually pressure engages the key fob buttons. The battery is an excellent point, if it would be at risk for overheating due to pressure on the battery alone. This is something that hadn't yet occurred to me and also why this forum is so great. I will do more research on this before advertising it safe for electronic fobs with batteries.

The recreational dive limit is 40m. At 40m, the relative (to the surface) pressure is very close to 40g per square mm (or 4 kilos per square centimetre) so measure your buttons and you'll know how much force they will experience.

I think you can see the potential for problems.

 

[Marlene996]

Good point.

@lowwall Also, if you are worried about the battery in your key, why not also the battery in your go pro, phone, or other camera at depth?