Linkert tool kit includes six special drill pivots with brass knurled handles, an idle shot tool, and a venturi tool for use on all years brass Linkert carburetor bodies. Drill bit sizes include #55 (1.3mm), #53 (1.5mm), #56 (1.2mm), #42 (2.3mm) and #72 (0.6mm). The #55 drill bit is used by two different length handles. Slot tool blade sizes include .017" and .009" for all carburetors. The 1 3/16" collar is used for M-4, ll, 16, and 18 carburetors. The 1 3/8" collar is used for M-2, 5, 6, 21, 31, 41, 41L, 42, 51, 51L, 52, 54, 54B, 55, 58, 64, 84, 88, 90, 97, 341, 343, 344, 350, 352, and 641 carburetors. The 1 9/16" collar is used for M-35, 35T, 35TP, 36, 36A, 45, 45A, 61, 61B, 74, and 74B carburetors. Note that drills and tool blades are for hand use only. The use of an arbor or hydraulic press is recommended.