Akeda 3809 is a 9 Degree Dovetail Cutter Router Bit. This Akeda 9º x 5/8-Inch deep dovetail bit with 8mm shank is used with the 9º pin guides to form through dovetails from 5/8-Inch down to 1/4-Inch thick. It is also used to form fixed depth (5/8-Inch) half blind dovetails using the guide fingers included with the jig. This bit has an 8mm shank, so you may need a 1/2-Inch to 8mm collet reducer for your router.