Jetting products are NOT returnable-these are tuning parts therefore no returns or exchanges. If planning on returning jets please order from another place that sells used, drilled out and counterfeit jets. There are too many variables to ensure the jets listed below will fit the carb. Pull the jets from the carb and measure them first. If incorrect jets are ordered it will be unpleasant when they arrive, just delay the tuning process, waste time, be frustrating, still wont have the correct jet and will end up measuring in the end. We have advised to measure, if advice is ignored the frustration is your fault, don't blindly purchase jets like a novice. MEASURE YOUR JETS, cant figure it out see our FAQ extreme top left of page and read "identify that jet" link. things to check before ordering.
Keihin slow 3J-xxx

3J Keihin jets - price each
jet keihin slow
OVERALL LENGTH = 28mm
DIAMETER OF THICKEST PART = 5mm
THREAD DIAMETER = 4.9mm

Keihin jet size 38 $6.79
Keihin jet size 40 $6.79
Keihin jet size 42 $6.79