SIZE. Downcut spiral router bit with 1/4" cutting diameter; 1" cutting length; 1/4" shank; 2-1/2" overall length, can be used on CNC, engraving machine, router table and hand-held machine. DLC COATING. The TAC coating provide up to 2.5 times life than the uncoated. Higher hardness and more heat resistance, making the CNC router bit smooth stable, sturdy durable. DOWNCUT. Spiral router bits used for smoothly upcut groove and slots, Mortises, Cycles and dados leave with clean Edge and Bottom surface, better than straight bits. APPLICATION. This CNC End Mill Router Bits is perfect for soft woods, hard woods, Plywood, laminate, OAK, MDF, hard woods and aluminum. Perfect for 2D/3D wood carving or engraving. CNC spiral router end mill bit are Suitable for side milling, end milling, finish machining. SOLID CARBIDE. This provides longevity and produces cutting results of the highest quality. Clean surface, neat, no glitches.