Lengthened size-Perfect for stair stringers layout, rafter layout, etc.Easy layout on any material, especially when there are Crevice in the edge of the wood. Patented product. Recessed cutout-Align with the ruler marks on the frame square, the ruler marks can be seen through the concave cut when the gague is fully inserted,increase visual field area. Dedicated storage-The gauge is equipped with steel wire rope to a dedicated storage place to prevent loss.They are also very light and easy to .It can be hung on the work bag, magnetic tool storage panel and storage rack. Made of anodized aluminum alloy. Hexagonal plane is more frictional and can work better. Multiple functions-Stair stringers and Rafter layout - Rip guide for circular saw - Framing square attachment - Using on to repetitive angles - Using on to guide saw to make angle cuts Material:Aluminum alloy colour:blue Package Contents: 2 * Auxiliary Clip Square Ruler Only the above package content, other are not included. Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.