Internal metric size rings with tapered design. Maintain constant pressure to prevent slippage of axles, gears and bearings inside machinery housing. Handy kit for shop toolroom or toolbox. On hand when needed saves time and money. Plastic compartment box is easy to store. The Precision Brand 218-piece metric housing ring Assortment contains: (20) 10 mm, (15) 11 mm, (20) 12 mm, (18) 14 mm, (15) 15 mm, (18) 16 mm, (12) 18 mm, (10) 19 mm, (12) 20 mm, (10) 22 mm, (10) 24 mm, (8) 25 mm, (5) 26 mm, (8) 28 mm, (8) 30 mm, (8) 32 mm, (5) 35 mm, (3) 36 mm, (3) 37 mm, (5) 38 mm and (5) 40 mm.