The 7-1/2° dovetail Bit is used with both omnijig & the Incra Dovetail system., #45820, diameter (D) 1/4, angle (a°) 7.5°, cutting Height (B) 5/16, shank (D) 1/4, overall length (L) 2-1/2, Type Incra/omnijig 43659, flutes 2, Carbide Tipped Dovetail 7-1/2 deg X 1/4 dia x 5/16 x 1/4 inch Shank for omnijig & Incra