The heaviest strap-on I've owned would be the Kanati (Dual-Arc model, I think) which had hardware that allowed adjusting the angle of the hood as well as gripper. The were well made and sold through Anneewakee Archery. Some folks have had trouble contacting them of late, so I don't know if they're still in business. I think I heard somewhere the owner(John Dill) is working at a Marina on the N.C. coast, but can still be reached through Facebook. I think most makers offer different sized gripper options