Bearings used are either oil bearings or magnetic bearings. The steel axles are mounted in adjustable ball bearings. It consists of an axle, bearings and a hub shell. It is held by a stainless steel shaft with roller bearings. Friction welding may unintentionally occur at sliding surfaces like bearings. A lack of bearings and gears eliminates frictional inefficiencies and noise. Dry lubricants are often used in applications such as locks or dry lubricated bearings. The B18 furnished the P1800 with a strong engine boasting five main crankshaft bearings. UHMWPE is also used in the manufacture of hydraulic seals and bearings. It holds the steel bearings for the barrel lugs and the guide rods. Powell continues to make skateboard products, including Bones Bearings and skateboard wheels. Elastomeric bearings may also be used in place of conventional roller bearings. All big end bearings are lubricated this way. First ball bearings and bicycle hubs were made. The headstock contains high-precision spinning bearings.