Great value - double tongue & groove router bit set The Standard Tongue & Groove Router Bits will cut perfectly fitted tongue and groove joints ideal for wood flooring, wainscot panelling and shaker style panel doors. Use with 3/4" stock. Highest quality, 3 wing carbide cutters with premium enclosed ball bearings. The V-notch Tongue & Groove Router Bits set will cut perfectly fitted v-groove (tongue & groove) joints ideal for flooring and wainscot panelling. Use with 5/8" – 1-1/8" stock. 2 flute carbide cutters with premium enclosed ball bearings. Tongue & groove joints give extra gluing surface for extra-strong joints. Separate tongue and groove bits eliminate reassembly for each cut. A tongue and groove joint is the ideal way to create flat, even joints for flooring, wainscoting, panels and tabletops. Tongue and groove router bits will cut the 2 mating profiles for this easy to make woodworking joint with ease and with a simple setup. This joint also provides a lot of gluing surface as well as aligning ease. Tongue and groove bits can take quite a big bite out of the wood, so using these bits in a router table is strongly recommended. Even though some smaller tongue and groove bits can be utilized in a hand-held router the stability of a table will help keep the joint perfectly square. For best results, use with solid wood only.