Amana Tool Solid Carbide Spiral CNC Router Bits End Mills for Steel & Stainless Steel Flat Panel These two sets include bits These two sets include bits that match up to the actual thickness of 1 4" Freud's huge selection of carbide tipped and solid carbide double flute straight bits are ideal for grooving Superior cutting quality and extended tool life These router bits are manufactured from our exclusive ultra fine micrograin carbide and feature a 30 degree Center Cutting Mill End with a 45 degree corner chamfer (for extra strength) up cut design and very importantly Aluminum Titanium Nitride (AlTiN) coating for superior cut quality