Item Type: Stair Gauge Knob Material: Aluminium Alloy Purpose: Rafter Gauge Clamp Package List 1 x Stair Gauge Knob 1Hexagonal Shape: The hexagonal shape design fits better on the edges, can be completely perpendicular to the material, providing stable and accurate clamping for workpieces. 2Thumb Screw: The stair gauge comes with a black stainless steel thumb screw that is anti slip, durable, and easy to grip and tighten onto any rafter, even when wearing gloves. 3Main Applications: The stair gauge is mainly used for designing stair and beam structures. Its compact size makes it easy to store and transport. 4Practical in Use: Gives you an accurate framing jig and very precise layout, sturdy structure helps ensure the strength and durability. 5Quality Material: The stair gauge is made of high strength aluminum alloy material with an anodized surface that is wear resistant, corrosion resistant, and durable.