<b>Specifications:</b> Material: Durable steel<br> Shank Diameter: 1/2 Inch (12.7mm)<br> Hold Diameter: 1/2 Inch (12.7mm)<br> ER20 spring collet : 6.35mm/ 1/4 inch<br> ER20 spring collet : 12.7mm/ 1/2 inch<br> Wrench Spanner: ER20 M Type; High Carbon Steel; Anti-slip handle Design<br></p> <b>Package Included:</b><br> 1 * Router Collet Extension<br> 1 * 1/2’’ER20<br> 1 * 1/4’’ER20<br> 1 * ER20 M Type Collet Chuck Wrench Spanner