Specification Brand : HARFINGTON BulletPoint1 : Size - 2 pieces of nylon guide pulley rolling bearing, fits for 5mm shaft diameter. BulletPoint2 : Material - Chrome steel (GCr15) bearing and nylon guide rail, high hardness, and great wear resistance showing stable performance and lasting service life. BulletPoint3 : Features - Both sides are rubber sealed, oil- and liquid-resistant, keeping stable and smooth operation. BulletPoint4 : Applications - U-type pulley bearing fits the rail track system. Widely used in doors and window to track and drive mechanical equipment. Suitable for sliding barn doors, automatic mobile doors, aluminum doors, pulleys and drawers, wheelbarrows, garden carts, etc BulletPoint5 : Dimension - 5mm(Inner Dia) x 40mm(Outer Dia) x 20mm(Thickness); groove width: 16mm, groove depth: 8mm Color : Black ExternallyAssignedProductIdentifier : 4894878077273 IncludedComponents : Deep Groove Ball bearing ItemName : HARFINGTON 2pcs U Groove Pulley Bearings Nylon Guide Roller Bearing 5x40x20mm U Groove Pulley Wheel for Doors Window, Black ItemPackageDimensions_Height : 18.5 centimeters ItemPackageDimensions_Length : 3.6 centimeters ItemPackageDimensions_Width : 6.9 centimeters ItemPackageQuantity : 1 ItemShape : Round ItemTypeKeyword : deep-groove-ball-bearings Manufacturer : HARFINGTON Material : Alloy Steel ModelNumber : BORDSTRACT48megrcw0u NumberOfItems : 2 PackageLevel : unit PartNumber : hta221010hh1219 ProductDescription : Size: 2 pieces of nylon guide pulley rolling bearing, fits for 5mm shaft diameter. Chrome steel (GCr15) bearing and nylon guide rail, high hardness, and great wear resistance showing stable performance and lasting service life. U-type pulley bearing fits the rail track system. Widely used in doors and window to track and drive mechanical equipment. Suitable for sliding barn doors, automatic mobile doors, aluminum doors, pulleys and drawers, wheelbarrows, garden carts, etc. Both sides are rubber sealed, oil- and liquid-resistant, keeping stable and smooth operation. Dimension: 5mm(Inner Dia) x 40mm(Outer Dia) x 20mm(Thickness); groove width: 16mm, groove depth: 8mm