Sleeve tool steel tools than precise size, tensile strength, abrasion resistance and good. Surface treatment is a surface painted black, one is gray hammer surface coating. Heavy sleeve metric and imperial points, although the sleeve concave shape like a concave hexagon socket head is cylindrical, hexagonal inner sleeve bolt arranged sequentially depending on the model, you can choose according to need. It refers socket wrench head sleeve short. In simple terms it is a special tool to tighten loose screws or unloading, designed to pull tighten hexagonal nut threaded fasteners. Require special hand tools according to plan or intention to make the production of construction. And civilian differentiated hardware tools. Higher hardness, size bigger and thicker, the scope is more extensive. Steel wrench, steel tap wrench, tap wrench steel, special sleeve, steel F spanner, steel hexagonal crowbar. ! Top, thimble, needle, and so listen to special tools: the introduction of German technology, in line with the German DIN7444 standard (GD / T4388-1995, GB / T4389-1995, GB / T43390-1995) using high-quality alloy steel, die forging forming a workpiece by forging and rolling through 630-1600T large Moroccan press made