No Flat Tires And Wheel Assemblies for Z500 and Z900 Series ZTrak Replaces TCA13769. Heavy Duty Wheels – 440lbs max – Powder Coated Yellow – High Speed Tapered Roller Bearings 6204-2RS. Smooth Flat Free Tires 13×5.00-6 Axle Width 5-5/8″ Center hole: 5/8″. Grease Zerk included, tires must be greased before use. Fits Quik-Trak 647A, 657A, 667A & ZTrak Z510A, Z520A, Z710A, Z720A, Z915B, Z915E, 717A, 727A, 737, 757. Please check model number to get part number for fitment, if you have trouble, send us model number and we will make sure it will fit. If the item is found to be defective the customer may send the part back for inspection from Provenpart, if the part is considered to have a material defect Provenpart will send the customer at no charge a replacement part.