After an extended period of development and testing, SubGravity has released a new, more optimized and economical flapper / mushroom / one-way valve. These new valves are manufactured by SubGravity, and are drop in replacements for the previously used Drager valves. Pair (2) of one-way valves for shrimp BOV Will also work in the Golem Gear / iQsub DSVs (both classic and sidemount) Will also work in any BOV or DSV that calls for the use of the clear Drager mushroom valves Clear valves only (no delrin assembly)