uxcell Milling Chuck Lathe Tool Part Spring Collet Clamping Nuts ER11 Product Name : Collet Nuts;Model : ER11 Hole Diameter : 9mm/ 0.4";Thread Diameter : 13mm/ 0.5" Overall Size(Approx.) : 15 x 12mm/ 0.6" x 0.5" (D*L);Material : Metal Color : Black;Net Weight : 9g Package : 1 x Collet Nuts