Extra D-rings make it easier to tie gear in a raft or canoe or to add grab lines for safety. These D-ring patches are made of sewn and glued Hypalon and Neoprene. Smaller 4-1/2" D-ring patch uses a 1" ring secured by a length of 1" nylon, also sewn to a base of raft floor material. Surface patches are Hypalon in dark or light gray, royal blue, red, and Avon gray. Large patches are strong enough to be used as rowing frame tie-downs.