Just had the pleasure of opening up one of the just released Scubapro Mk 21's at the DEMA Service Seminar. The Mk 21 is being marketed as a lesser priced alternative to the Mk 25, and I think they've hit all the marks.
This think looks like it could be a real sweet first stage! The internals are right from the Mk 25, and incorporate all the ice-shedding features that make it among the best cold water pistons: the TIS sleeve around the piston shaft, a second wiper o-ring, and the plastic spacer above the piston head.
From a cost-saving standpoint (and maybe a theoretical "failure-point" standpoint) the swivel turret has been replaced by one of two fixed heads held in place by TORX screws that come off at either 30 degrees or 45 degrees depending upon what you want. Haven't seen it, but I hear the 45-degree head also has an end port for super high flow. From a designer who's supposedly a Ducati rider back in Italy, we see a pretty snazzy looking case design reminiscent of a motorcycle cylinder head. The heat absorptive capability of those fins is not insignificant re: freezing. They're not just for looks.
Of course, the IP is externally adjustable with the hex screw on the right side of the picture, just like the Mk 25.
The very cool looks aside, I think this is indeed going to be a Mk 25 performer at about $100 less in retail cost. If you have to have a swivel, this one is not for you.
Those who've seen my posts won't classify me as a Scubapro fanboy, even though I service them regularly. I'm an equal opportunity critic, lol! But I felt privileged to be able to take this one apart - I think it's going to be fantastic!
This think looks like it could be a real sweet first stage! The internals are right from the Mk 25, and incorporate all the ice-shedding features that make it among the best cold water pistons: the TIS sleeve around the piston shaft, a second wiper o-ring, and the plastic spacer above the piston head.
From a cost-saving standpoint (and maybe a theoretical "failure-point" standpoint) the swivel turret has been replaced by one of two fixed heads held in place by TORX screws that come off at either 30 degrees or 45 degrees depending upon what you want. Haven't seen it, but I hear the 45-degree head also has an end port for super high flow. From a designer who's supposedly a Ducati rider back in Italy, we see a pretty snazzy looking case design reminiscent of a motorcycle cylinder head. The heat absorptive capability of those fins is not insignificant re: freezing. They're not just for looks.
Of course, the IP is externally adjustable with the hex screw on the right side of the picture, just like the Mk 25.
The very cool looks aside, I think this is indeed going to be a Mk 25 performer at about $100 less in retail cost. If you have to have a swivel, this one is not for you.
Those who've seen my posts won't classify me as a Scubapro fanboy, even though I service them regularly. I'm an equal opportunity critic, lol! But I felt privileged to be able to take this one apart - I think it's going to be fantastic!
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