In a world first OSEL are quite happy to disclose that they are now supplying their rebreather valves with a progressively opening cylinder valve seat.
This is available as a free of cost safety upgrade during annual service for all Apocalypse Type IV CCR owners and can be bought with the NAUTEC valves OSEL supply. The two types OSEL offer in G5/8 and M26 are the T valve and the K valve, with the plastic knob.
For further details see https://www.facebook.com/OpenSafety....type=3&theater
To buy contact OSEL at email@example.com