Inner Barrel Spacer for sniper rifles. Made of durable polyacetal (POM) with two inner and two outer O-rings. Main purpose is to keep barrel in exact axle position. It will improove accuracy of your shooting. Instalation doesn`t require any modification and is easy. Outer diameter is around 26mm si it is dedicated for the larger barrels like: Tokyo Marui AWS series, and Well MB4401, 4404, 4406, 4408, 4410. Packing include 2 pcs.