Made by imbedding high quality diamond into a shank body of certain specification, it makes use of the natural sharp angle of natural diamond and carry forward the surface-hardness and abrasive resistance of natural diamond. It fits for the precision dressing of grinder abrasion wheel with large diameter and granularity, and it also fits for the dressing of the common abrasion wheel. The grade contains:1,2,3 level. The specification contains 0.3Ct- 3Ct,etc. The main type: ND10# ND22# ND33# ND44# ND55# ND100# ND200# .