1 NOS Rear Idler Wheels for the 75 Polaris TX, 75, 76, 77 Electra, 78 79 Cobra and 79 Apollo. May well fit many others. These are actual Polaris parts, part number 1594021. They are about 6, 3/8" with a 1" ID. They will have dust and dirt and shelf wear, but are new old stock.