Feature: 1. 10Pcs in 1 Set: The kit contains 10pcs ER16 spring collets of different models, suitable for different processing scenarios. 2. Durable Material: These collets are made of excellent high speed steel material (HSS) and have good rust and corrosion resistance. 3. With Wrench: Equipped with a suitable wrench, it is easy to use and adjust the collet, no other tools are needed. 4. Multiple Usages: Used in various machining applications, including boring, milling, reaming, tapping and grinding, etc. 5. Convenient Storage: These spring collets are stored in a plastic box, which is small and portable, easy to store and carry. Specification: Item Type: Collet Chuck Set Product Material: High speed steel Collet Model: ER16-1, ER16-2, ER16-3, ER16-4, ER16-5, ER16-6, ER16-7, ER16-8, ER16-9, ER16-10 Product Model: SKER1610PC03 Wrench Size: Approx. 8 x 30 x 138mm / 0.3 x 1.2 x 5.4in Model Outside Diameter Approx. Inside Diameter Approx. ER16-1 17mm / 0.7in 1mm / 0.04in ER16-2 17mm / 0.7in 2mm / 0.08in ER16-3 17mm / 0.7in 3mm / 0.12in ER16-4 17mm / 0.7in 4mm / 0.16in ER16-5 17mm / 0.7in 5mm / 0.2in ER16-6 17mm / 0.7in 6mm / 0.24in ER16-7 17mm / 0.7in 7mm / 0.28in ER16-8 17mm / 0.7in 8mm / 0.31in ER16-9 17mm / 0.7in 9mm / 0.35in ER16-10 17mm / 0.7in 10mm / 0.39in . Package List: 1 x ER16-1 Collet1 x ER16-2 Collet1 x ER16-3 Collet1 x ER16-4 Collet1 x ER16-5 Collet1 x ER16-6 Collet1 x ER16-7 Collet1 x ER16-8 Collet1 x ER16-9 Collet1 x ER16-10 Collet1 x Wrench