This is the ScubaPro S-TEK Fluid Form Weight System Pockets Features: Easily mounts onto the harness waist strap. Includes two MonpreneA(R) weight holsters in black and two ditchable weight pockets. Weight pockets each hold up to 11lbs/5kg of ballast weight. Compatible with HYDROS Color Kits, Knife Mount, Mini-D-Rings and Ninja Pocket. The S-Tek Pro Fluid Form Weight System is a weight pocket kit that makes it simple to add an integrated weight system to a S-Tek Pro Harness.