Established in 1982, Hangzhou Xianshan Changyu Metal Machinery Co., Ltd. specializedin various kinds of hardware tools with its more than 30 years' experience. it is one of theearliest carbide hole saw manufacturers with professional staff set research anddevelopment together.It covers more than one hundred products and mainly the Multi-function saw blade, Hardalloy saw blade, Diamond hole saw, Tungsten carbide grit hole saw. Carbide coated fileCarbide grit rod saw, Tungsten carbide grit blades, Carbide grit jig saw blade, Bi-Metahole saw which are popular in European and America markets such