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. The 8" model has a 2" plated steel ring held by a crow's foot of 2" nylon, sewn to a circle of heavy raft floor material and glued to the back of the patch. 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.