I have been using the Vang product for over ten years. They are on multiple of my 14 inch 870 shotguns that have banged around boats and planes in Alaska. I believe the design was inspired by Bill Jeans, now retired, of Morrigan Consulting. Bill was formerly head of Gunsite, under Jeff, before branching out onto his own as ownership changed there. I always put Velcro on the shotgun and stuck them to that. Particularly well suited to an inertial Benelli that doesn’t always do well with things bolted to the receiver.