This compact SMB (surface marker buoy) folds into a small package for easy stowing while diving, then deploys quickly once you reach the surface. Made of rugged 210D nylon or PVC with HF welded seams, the bottom is sealed and a metal inflator and 42mm exhaust valve are included. There's a stainless D-ring and bungee loop on the lower end, with a plastic D-ring on top for a flashlight.