Usage Tips:[Premium Material]-- Made from durable PU material, designed to provide good grip and speed in all hardnesses and has excellent durability. [Size & Diameter]-- 58mm in diameter, 32mm in width, equipped with ABEC 9 bearings and spacer, the inner diameter of bearing is 8mm, outer diameter of bearing is 22mm, please if it is the specifications you need before purchasing. Bearings and spacers are already installed on the wheel. [82A Hardness for Outdoor Performance]-- With 82A hardness, providing balance of grip and softness, these wheels are soft enough that you don't feel every bump, but roll as smoothly as any other hybrid wheel, great to skate on hard or rough outdoor surfaces. []-- These softer wheels are better for outdoors because they have more "give" to allow you to bounce or roll over small sticks, cracks, and rocks. Also a decent for beginner skaters on slick/hard surfaces because the soft wheel makes the fairly slow and steady. Colour:black Material:PU Size:58mm in diameter, 32mm in width Package Contents: 8 * skate wheel 1 * wrench Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.