IRWIN Tools VISE-GRIP Locking Pliers, Original, 4-Piece Set (71) Ideal for tightening, clamping, twisting and turning. Classic trigger release provides maximum locking force. Constructed of high-grade heat-treated alloy steel for maximum toughness and durability. Adjust pressure and work fit with turn screw that stays adjusted for repetitive use. 4-piece set in kit bag includes 1 each of the following: 10CR, 7R, 6LN, and 5WR.