Automatic swimming pool cleaners and parts therefor; Belts for farm vehicle machines; Dust filters and bags for vacuum cleaners; Internal combustion engine parts, namely, piston rings; Land vehicle parts, namely, spark plug wires; Machine parts, namely, joints and joint parts for connecting sliding strips, plates and guides; Machine parts, namely, mechanical seals; Machine parts, namely, metal grounding bushings; Machine parts, namely, rollers coated with synthetic material; Machine parts, namely, wear plates and strips; Pond and water garden aeration systems comprising water pumps, air compressors, air blowers and a finned wheel for pressurizing and aerating ponds and aquariums; Power-operated screwdrivers; Power tool parts, namely, pumps; 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; Vacuum cleaner bags