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 -resistant, suitable for 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. Suitable for steel ruler with thickness of 0-3mm and width of 0-30mm. Name: steel rule limit adjustment positioning block Colour:yellow+red Material:aluminum alloy Package Contents: 2 x Steel ruler limit 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.