Koken 3 4"Dr Socket 12 point 42mm Standard Impact Useful for both alignment and Useful for both alignment and for measurement purposes Mitutoyo proprietary new design permits smooth pointer operation Flat crystal makes graduations easy to read Strong frame provides excellent rigidity and durability Non magnetic pointer and contact point permit reliable operation even in magnetic environments Clear and concise wide dial face allows excellent visibility The surface of the crystal is hard coated for excellent scratch resistance O ring protection guarding against oil and water penetration Protects against scale build up please go by the product title when purchasing Please note: Some product images do not match the product title