Roman Carbide Groove Cut Flooring 3/4in Bore. Designed for use with 5/8 inch and 3/4 inch lumber these cutters are great for designing new floors or for creating replacement planks. Tongue and groove are below center so you can resand and finish a number of times. Package Contents: Roman Carbide Groove Cut Flooring Bore Roman Carbide DC2305 Groove Cut Flooring 3/4in Bore