In previous tests ScubaLab drysuit included test results for the flow valve (the ability of the exhaust more air flow demand of the inlet valve can be put in). This is obviously a security issue but also one of the simple functionality. However, recent evidence has shown ScubaLab rate a drysuit valve flow is affected by several variables: It seems that the rate of flow of any given valve can vary considerably depending on the underwear, in the form of dress, positioning / location of the valve and even the weight of the diver. Basically, any two divers can find very different results. In fact, the same diver may experience different results with different clothes. Of course, it remains crucial that manufacturers offer more exhaust valves gas inlet valve put in, but to ensure safety, the divers use dry suits that fit and wear underwear that does not trap air. Our recommendation: While using your normal underwear, get into the water with a dry suit before buying. You should be able to kneel upright, lift the arm of the valve so it is above the entry, then press and hold the dry suit inflator button for 15 seconds or less while breathing normally . You should not notice any positive buoyancy.