EBC Brakes CRK32A 64-Piece Hex Main Jet Kit for Keihin 99101-357 Carburetor High precision brass main jets for Keihin carburetors using 99101-357 hex style main jets Kit contains 2 pieces each jet sizes 80 thru 158 for a total of 64 jets Keihin 99101-357 hex main jets measure 16.5mm long (10mm hex body length/6mm thread length) EBC main jets are precise, clearly marked and reliably gauged using pin gauges, and accurate to one tenth of a thousandth of an inch All jets are flow calibrated and extremely accurate in terms of fuel flow rate as stamped