36" adjustable bar clamp Screws have 1/2" acme thread Made of extruded and injection molded aluminum alloys This 36" universal bar clamp is made of high quality extruded aluminum for both light weight and strength. The head of the clamp is riveted for rigidity and the adjustable foot wraps fully around the bar for tight clamping action. Detents are spaced 5/8" apart for quick adjustments. The clamp sits upright and is well balanced for ease of use. These clamps have a large “wing” type knob for good clamping pressure without causing fatigue.