Specification Brand : Felixstory BulletPoint1 : 8.5x2.125 inch solid tire size: Outer Diameter - approx. 21cm / 8.26in; Inner Diameter - approx.13.7cm/5.39in. Tire groove width- 3.7cm/1.45 inch. Tread width 5.4cm/2.125 inch. Please see pictures to confirm size before order. The actual outside diameter of the tire is not enough for 8.5 inch, 8.5 inch is the size of the tire when mounted to the wheel. Please don't worry BulletPoint2 : Applicable E-scooter model: Our 8.5x2.125 solid off-road tires are suitable for replacing original tires in sizes 8.5x2.0", 8 1/2x2", 50/75-6.1. Suitable for scooters with 6" wheels hub such as: Gotrax GXL V2/ XR/ Apex XL, Hiboy S2/ S2R Plus, Hover 1,Xiaomi M365/Pro, Aovopro ES80, VSETT 8/9/9+, Zero 9, Swagtron Swagger 5, Inokim Light 2, Dualtron Mini, iScooter 1S i9s,HURES18-M5 VOLPAM SP06 AOVOPRO ES80 Aovowheel ES7-01etc. See pictures for more models BulletPoint3 : Maintenance free: Our 8.5x2.125-6.1 scooter tires are solid, no air leakage, no need to check tire pressure and inflation regularly. Compared to pneumatic tires, solid tires dissipate heat better. Solid tires usually last 2-3 times longer than pneumatic tires. No flat tires, wear-resistant and puncture-resistant. Reduces maintenance costs BulletPoint4 : Honeycomb Design: Our 8.5x2.125 off road tire lighter and less stiff than full/filled solid tires. Shock absorption is better than full solid tires. Anti-skid pattern design, suitable for stone pavement road, mud road, raining road, uneven road, irregular road. Can be used all year round BulletPoint5 : Quality Guarantee: The 8.5 x 2.125 scooter tire focuses on customer experience. Felixstory always produces high quality tires in the market. Regarding the product problem, such as the size does not fit, can not be installed, etc. please send a message to us, we are happy to help you solve the problem Color : 8.5x2.125 solid tire CompatibleWithVehicleType : Scooter ConstructionType : Solid Department : unisex-adult ExteriorFinish : NO ExternallyAssignedProductIdentifier1 : 194488078252 ExternallyAssignedProductIdentifier2 : 0194488078252 GpsrSafetyAttestation : 1 HoleCount : 1 ImportDesignation : Imported IncludedComponents : 8 inline skate wheels ItemName : Felixstory 8.5x2.125 Off Road Solid Tire, 50/75-6.1 Scooter Tire Fit for Gotrax GXL V2 XR Apex XL Rival Hiboy S2 Hover 1 iScooter Electric Scooter Replacement Wheels, 8.5x2.0 inch 8 1/2x2 Tyre ItemPackageDimensions_Height : 22.8092 centimeters ItemPackageDimensions_Length : 6.1976 centimeters ItemPackageDimensions_Width : 22.4028 centimeters ItemPackageQuantity : 1 ItemTypeKeyword : sports-scooter-wheels LoadCapacity : 190 kilograms LoadIndex : 87 Manufacturer : Felixstory Material : Rubber MaximumPressure : 50 pounds_per_square_inch MaximumWeightRecommendation : 0.26 kilograms ModelName : 8.5x2.125 solid tire ModelNumber : 8.5x2.125 solid tire NumberOfItems : 1 PackageLevel : unit PartNumber : 8.5x2.125 solid tire Ply : 4 ProductDescription : ProductSiteLaunchDate : 2024-01-02T08:00:00.000Z Seasons : Year Round SectionWidth : 1.41 inches Size : 8.5x2.125 inch SoleMaterial : Polyurethane SpecificUsesForProduct : indoor outdoor scooter riding SpeedRating : H StreetDate : 2024-02-27T00:00:01Z Style : Inline Skates SupplierDeclaredDgHzRegulation : not_applicable SupplierDeclaredHasProductIdentifierExemption : 1 UnitCount : 2 UnspscCode : 25172500 VehicleTireIsoMetricSizeDescription : 54/4R6.1 WarrantyDescription : 1 year limited warranty WebsiteShippingWeight : 0.848 kilograms