For Zeagle's Metal Backplate Adjustable quick release Tow cable attachments The 519-CS01 Crotch Strap can be used on all Zeagle metal backplates and any Zeagle BC (Ranger, Tech, etc.) that has a 1" tri-bar at the bottom of the vest section back. It has a 1" ring to attach to a towing fixture of a DPV (Diver Propulsion Vehicle).