Skid-steer loaders; Rubber tracks being parts of crawlers on loading-unloading machines and apparatus; Self-lubricating mechanical friction parts, especially of composite materials, namely, wear rings, washers, bushings, spherical bearings, bearing pads, sliding blocks and machine transmission gears all for load bearing machines, conveyors, handling trucks and machines, lifting machines, agricultural machinery, construction equipment machines and hydraulic turbines; Wheel loaders; Rubber trac...