Holley Main Jets 66 #122-66 4340000 11mm4112n - 1/2" dr attack

11mm4112n - 1/2" dr attack driver4138 - 1/2" dr bit holder

#4 Morse Taper Shank

1 handle for chuck (Allen key supplied)

Overall length 90mm

Size: 1" x 2" x 8"

Holley Main Jets 66 #122-66 4340000 11mm4112n - 1/2" dr attackThese metering orifices control fuel flow into the metering system. They are rated in flow capacity cubic centimeters per minute and are changeable for tuning purposes. The shape of the entry, exit, and size determines flow. All Holley Main Jets are flow tested and then stamped with the correct number. Standard Main Jet . 066" Jet size 1 4 32 Thread Sizes from 40 110 Fits All Holley Model 2010, 2300, 4010, 4011, 4150, 4160 & 4500