Union Butterfield End Mill, Center Cutting, Double End, Regular Length, Square End, Series: 923, 5/8 in Cutter Dia, 5 in Overall Length, 1-1/8 in Maximum Depth of Cut, 2 Flutes, Spiral Flute, 5/8 in Shank Dia, Right Hand Cutting, 30 deg Helix Angle, Weld-On Flat Shank, HSS, Bright