This sale is for a new old stock, never been used Marvel Schebler TSX 389 carburetor. According to my book this fits Gibson tractors, but it does not elaborate. I am sure this is for a 6 cylinder model because of the size of the carburetor. The mounting holes measure 2-11/16" center to center, and the throttle bore measures 1-3/8" in diameter. Again, this carburetor has never been used. Please see pictures and 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. Illinois residents will add 8.25% Illinois sales tax, unless a valid Illinois resale tax number is provided. I will ship internationally and will combine shipping on multiple purchases.