Mk25 vs Mk21

[LanceRiley]

Both are piston type any major difference? aside from the swivel of the MK25

 

[tstormdiver]

Having breathed off of both, the breathing difference is minimal between the 2. Biggest differences in the 1st stages is the MK21 piston is slightly smaller & the MK25 has a swiveling bottom & 5 low pressure ports , for more hose routing options whereas the MK21 is fixed with 4 low pressure ports

 

[LanceRiley]

Having breathed off of both, the breathing difference is minimal between the 2. Biggest differences in the 1st stages is the MK21 piston is slightly smaller & the MK25 has a swiveling bottom & 5 low pressure ports , for more hose routing options whereas the MK21 is fixed with 4 low pressure ports

hi tstormdiver,

ive been diving since 2011. but stopped in 2014 due to health.. Now that im back in shape... i'm going back diving! and to boot managed to bring along new friends introducing them to diving =)

Im asking because when i started diving there was just the MK25 and MK17. I bought the MK17 for warm water diving single tank.. and I was wondering if what I'll ask my friends to buy... mk21 or mk11 1st stage. Mk21 seems like a cheaper option compared to a MK25 after all they're going to be diving recreational.

 

[tstormdiver]

The MK21 will do anything you would want to do recreationally & be an excellent breather. Scubapro still has the MK17, which IMO is a step better than the MK11.Any of the 4 will serve you well. Going from best breathing, on down would be MK25, MK21, MK17, MK11. When Talking 2nd stages, The S600 & S560 are identical except the S560 has the old style plastic barrel & the S600 Has the metal barrel & more chrome decoration. For my Hollis 1st stages I got a pair of S560's because, being a cave diver, I tend to beat (Scratch) the hell out of my regulators, so the chrome is of no meaning to me. What counts is ease of breathing. The S360 is somewhat similar to the S560, but does not have the adjustment knob, so all adjustments must be made during servicing.