The S-Max M series contra-angles have dramatically improved durability, and feature an updated internal body design and chuck mechanism. They are NSK’s next-generation standard – a marriage of ergonomic sophistication and smooth cutting feel. Specifications: 1:5 Increasing Max Speed: 200,000 min-1 Head Size: Ø9.9 x H 14.5 mm For: FG Burs (Ø1.6) Stainless Steel Quattro Spray Features: Anti Heat System Cellular Glass Optics Ceramic Bearings Clean Head System Push Button Chuck.