Racing Kart, Clone, Predator, Hemi, Honda, Briggs, BSP most Motorcycles or engines if they have a 4.5, 5, 5.5, 6,7 mm , 1/4" mm valve stem, If you are building or rebuilding your own small engines, either for performance or just a quality rebuild, this gives you control of cutting your own valve seats you can do a standard 45 degree seat or even 3 angle seat with this set... you can move the sealing surface on the seat for best performance... this is ONLY if you have 4.5, 5, 5.5, 6,7 mm , 1/4" valve stems this kit comes with the following. Valve Seat Cutter Kit Carbide Tipped 3 Angle Cut As Original Seat Milling In The Following Sizes 1st Top Angle & 2nd Base Angel Cutters Valve seat cutters: 22 mm 30 Degree & 45 degree 23 mm 30 Degree & 45 degree 24 mm 30 Degree & 45 degree 25 mm 30 Degree & 45 degree 26 mm 30 Degree & 45 degree 27 mm 30 Degree & 45 degree 28 mm 30 Degree & 45 degree 29 mm 30 Degree & 45 degree 30 mm 30 Degree & 45 degree 32 mm 30 Degree & 45 degree 34 mm 30 Degree & 45 degree 3rd Throat Angle Cutters 23 mm 60 degree 25 mm 60 degree 28 mm 60 degree 30 mm 60 degree 32 mm 60 degree 30 Degree & 45 Degree Cutters are Usable From Both Side As Other Side Is Grounded At 90 Degree. 6 Stem Guide's Sizes 4.5 MM - 5 MM - 5.5 MM - 6 MM - 7 MM - 1/4" 6 High Speed Steel Reamer's Size 4.5 MM - 5 MM - 5.5 MM - 6 MM - 7 MM - 1/4" 2 Arbor 2 Drive Rod 1 Tap 3/8" UNF 24 TPI Total 44 Pcs Set  In A Vintage Style Wooden Box