This sale is for a rebuilt Marvel Schebler USX 21 carburetor. This carb has been taken completely apart and bead blasted and polished inside and out. Correct bits run through all circuits and blown out. New float, float valve, throttle shaft, diaphragm, gaskets, screws, and machine work done as needed. Tested for leakage and flow. Comes with mounting gasket and is ready to install. This is the correct carburetor to fit John Deere 3010, 3020, 4010 and 4020 tractors. Please see pictures. Ask questions if you have them. We describe our items as accurately as possible. We do not know everything, so look at the photos as well as reading description completely. I will ship internationally and will combine shipping on multiple purchases.