Holley carburetor chokes shaft assembly for most later models Holley Performance 2 and 4bbl carburetors. Holley list numbers 4412, 1850, 3310, 80457, 80508 4776, 4777, 4778, 4779, 4780 and many others. This assembly uses no screws to hold the choke plate in the shaft. The shaft length is 4.350 inches and the diameter is .315.Questions? Give us a call at 770-457-8570 or email [email protected]