Woodhaven 8541 4" Hinge Jig, 5/8" Radius 4" Hinge Jig, w/5/8" radius corners Fastest, easiest, least expensive and most accurate way to cut a hinge mortise. Clamps to work so there's no nail holes or other unsightly blemishes. Jig attaches to a 3/4" wood fence you supply with the included hardware. The fence provides chip-free cuts and easy indexing. Two screw-in indexing pins position the fence to the backset you want and insure it's square on the jig. Made of 10mm (.393) thick phenolic for heavy duty use, measures 5-5/8" x 7-5/8". Uses a bearing guided bit (our 8500 - sold separetly), or bushing & bit combination (5030K & 13416 - sold separately), to follow the jig for perfect mortises. Router & bit not included. Lifetime guarantee against defects in material or workmanship. Made in the USA!