Holley Standard Main Jets . Size 66 # HO122-66 Rate_10 They're calibrated to give you

They're calibrated to give you the performance that you need

reduce stretching and prevent slippage compared to traditional 6 Rib designs

Fits all GM LS engines equipped with LS3/L92-style rectangular port cylinder heads

as well as a kickdown lever for use with Ford transmissions

Holley Standard Main Jets . Size 66 # HO122-66 Rate_10 They're calibrated to give youHolley Standard Main Jets . Size 66 # HO122 66 GENUINE HOLLEY STANDARD MAIN JETS. SALE IS FOR A PACKET OF 2 JETS. Fine tune your carburetor for street or race conditions. These Holley standard main jets are just what you need to fine tune your carburetor for street or race. Threaded for easy installation and removal, Holley jets are manufactured to high tolerances for consistency.