Advancing Hydropump design to a new level, with a new valve and detachable handball, the Hydromax is the Hydropump for the man who is serious about getting the very best from his pump. Hydromax comes complete with all the accessories you could ask for.Designed for use in the shower or bath. 250% more efficient than air pumps. Maximum penis diameter 1.81 inches, Maximum penis length 7.08 inches.