Features 1、Made of YG6 alloy +45# carbon steel high-quality material, strong and durable 2、Industrial grade T-slot milling cutter head. The carbide tip has an of sharpness cutting edge, possess high hardness and long life 3、Solid hardened steel (45+hardness) body with backlash designs, possess high efficiency 4、Used on electric milling machine, engraving machine, trimming machine, CNC and other automatic milling machine. All drill shanks must be inserted full length into the collet 5、Used for wood slotting, trimming, practical and durable, saving both time and labor Specification Item Type: 4-Flute Router Bit Material: Cutter head YG6 alloy, cutter body 45# carbon steel Color: Green black Uses: Used for wood slotting and trimming 4-Piece Set Specification: 6x40x1/4, 6x40x5/16, 6x40x3/8, 6x40x1/2 Size: 6x40x5/16: Approx. 40mm / 1.6in 8mm / 0.3in 46mm / 1.8in 6mm / 0.2in 6x40x3/8: Approx. 9.52mm / 0.4in 8mm / 0.3in 40mm / 1.6in 48mm / 1.9in 6mm / 0.2in 6x40x1/4: Approx. 6.35mm / 0.3in 8mm / 0.3in 40mm / 1.6in 45mm / 1.8in 6mm / 0.2in 6x40x1/2: Approx. 12.7mm / 0.5in 8mm / 0.3in 40mm / 1.6in 50.8mm / 2in 6mm / 0.2in Package List 4 x 4-Flute Router Bit