Heavy Duty Quality: Made of high-strength 6061 aluminum alloy for durability and wear resistance. Clamp accommodates materials up to 4.5cm thick and features easy-to-release knobs tighten for quick installation or shrinkage of the material. Application: Simple structure, convenient operation, strong clamping force and wide range of applications. These fixtures are suitable for many carpentry and metalworking applications for mounting and workpiece positioning. Slide into the T-track and quickly secure it by turning the handle. Practical: The pliers can help carpentry in a variety of circumstances for clamping, including diagonal cut, notch, joint, wide angle and acute angle. Compact design perfect for use with T-slots on desktop CNC machines. Durable: stainless steel screws, very sturdy. Carefully selected material, wear-resistant and durable. This is a T" type drop rail stopper, wood positioning limiter and fixed clamping tool.