1、ANODIZED ALUMINUM ALLOY: Made of good quality aluminum alloy, the surface is anodized to prevent discoloration in high temperature environments. Bolts are not easy to break, durable, reusable, and easy to carry 2、11 TO 60IN LENGTH RANGE: The joints of stair ruler can be combined and stretched arbitrarily, the length can slide in the range of 11 to 60in(including width of ruler on both sides). Rulers on both sides of the stair tread gauge can measure 10in 3、ADJUSTABLE RULERS: The stair tread formwork tool measures the length and width of boards simultaneously, allowing all boards to meet the same specifications. The rulers on both sides of the stair fixture can be adjusted to suit the angle of the stairs 4、EASY TO OPERATE: Stair tread gauges and shelf layout tools are easy to operate and cut to perfection, tools can be locked securely in place with 4 knobs 5、SCOPE OF APPLICATION: Stair step measurement tool can be used to cut and measure stair steps, stair risers, shelves, windowsills, closet shelves and some angle layouts