MB Crunchproof In-Line Trap Swivels - The heaviest and smoothest operating swivel ever offered to the trapper. There is a BIG DIFFERENCE between this swivel and all the others! The body on this swivel is .105" thick. Coyotes and large dogs can’t close the Crunch Proof’s swivel body down on the J-hooks causing the swivel to freeze-up like others do. Recommended for any animal trapped in North America. Strong enough for the toughest wolf, wolverine, bear, or mountain lion if the #6 J-hooks are welded. J-hooks included.