Cut Stair stringers for the treads using this bit, #45813, diameter (D) 1, angle (a°) 7°, cutting Height (B) 7/8, shank (D) 1/2, overall length (L) 2-1/2, Type Stair tread, usage right hand, flutes 2, Carbide Tipped Stair tread r/H Dovetail 7 deg X 1 inch dia X 7/8 x 1/2 shank