characteristic The steel ruler positioning block has high strength and is not easy to wear after long-term use. Made of aluminum alloy, rust-proof and corrosion-resistant, suitable for various environments. Suitable for all kinds of steel rulers, high efficiency, and the structural ruler is not easy to separate. It can be quickly adjusted to any position of the ruler, and can be measured at any time when it is locked, transforming any steel ruler into a precise marking tool. describe Name: steel rule limit adjustment positioning block Material: aluminum alloy Color: red+silver Quantity: 2pcs Suitable for steel ruler with thickness of 0-3mm and width of 0-30mm. Package Contents: 2 x steel rule positioning block Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.