Carbon Steel (High Carbon) T-Bar Wood Working Clamps in Variable Lengths, 1-1/2" x 1-1/2" bar clamps for doors and panels are real heavyweights. The T-Track is composed of Carbon Steel, while the heads and spindles are made of SG iron. The T bar is excellently secured against bending and twisting with a material thickness of 5mm and remains straight under tension. For a rock-solid grasp, the claw of the moveable clamping head interacts with the deep notches placed 16 mm apart along the rail. The moveable heads easily glide along the rail. The fixed clamping head's two-inch spindle (60mm) has a travel of 150mm. The big smooth-turning screw allows for quick and effective one-handed clamping.