Feature: The product is made of high quality steel, with a firm structure and light weight. Suitable for opening the diameter is 5/6/7/8/9/10mm. Precise positioning makes your opening easy and precise. Can effectively improve the speed and quality of woodworking operations. Centerlines ensure accurate alignment when drilling into various surfaces Specification:Material: Steel, PlasticColor: Red; YellowSuitable open hole diameter: 5/6/7/8/9/10mmPackage list:1 * Open hole fixed base6 * Steel sleeve(5/6/7/8/9/10mm, each * 1)Notice:The actual product color may deviate from the photo due to light.There may be a slight deviation in the measurement of product.