Product Name: Groove Ball Wheel Bearings; Type: 6201RS * Materal: Carbon Steel, Rubber; Outer Diameter: 32mm / 1.259" * Inner Diameter: 12mm/ 0.472"; Thickness: 10mm/ 0.393" * Color: Silver Tone, Black; Weight: 69g * Package Content: 2 x Groove Ball Wheel Bearings