They took the time to find a part number for an old machine.
TIRE ASSY, SOLID, 16.0 X 3.5 2.00B Rear Solid Wheel Assembly 16 x 3.5" : Fits Tennant 510E
Fits Tennant 86026Collections: All, Ebay/Amazon Tennant 3-6-15, Floor Cleaning Equipment Parts | Shop Online, Newest Products, Non-Equipment Items for Sale, OEM & Aftermarket Floor Machine Parts, OEM Parts, OrderlyEmails - Recommended Products, Tennant OEM, Tennant Parts | OEM and Aftermarket Replacement Parts, Tennant Scrubber Parts, Tennant Small Equipment & Carpet Extractor Parts, Tennant Sweeper Parts, Tennant Sweeper/Scrubber Parts