These pliers are made of heat treated steel and nickel/chrome plated for strength and durability. Theses pliers will hold pipes securely. The design also allows for user to adjust the clamping pressure without releasing the pliers. 150mm SPECIFICATION Throat Depth:50mm Opening (min/max):40-65mm Weight:0.3Kg 280mm SPECIFICATION Throat Depth:90mm Opening (min/max):40-65mm Weight:0.9Kg