This Ikelite replacement square style o-ring is for the Substrobe 150, 225, 300 and 400. It is also for the Mdular H, Modular Super, Modular Video Lite 45 as well as the Ikelite K and Ikelite II lights. The o-ring resembling a thick rubber band is designed to establish a watertight seal when going underwater.
Manufactured to precision tolerances required to hold a pressure seal on your housing and made of elastomeric material, it provides the means by which a watertight seal is formed.
O-Ring care guide