20mm RF100A 3FL Variable Helix, Necked Weldon Flat Shank, Bright Carbide End Mill, 38mm LOC, 3mm Radius, 52mm Reach 38MM LOC,20MM SHANK,104MM OAL RF 100 A 3-Flute, Right Hand 39?/40?/41? Variable Helix, Right Hand Cut, Weldon Flat Shank, Standard Length, Extended Neck Relief, Center Cutting Carbide End Mill, 3.00mm Corner Radius, Bright Uncoated for Roughing and Finishing Aluminum & Aluminum Alloys, Brass, Bronze, Copper, Magnesium and Plastic Series 6729 Guhring Part #9067290200300