The green wheel CROSS 12SB-MG is a complete, pre-assembled and ready to insert 8 inch spare wheel that fits most Skikes and other cross skates on 8 inch base. The widely recommended Major Grip tire guarantees a high mileage, rare failures and comes with a full off-road tread. The wheel is specifically designed for all terrain use, uphill and downhill. 4-5 bars of air-pressure present a fair balance between suspension and grip.