7 Parts for machines and machine tools, namely, parts for engines and motors in the nature of engine cases and push rods, couplings for machines, gears of plastic for machines; machine parts, namely, plastic bearings and valves for installation construction; machine parts, namely, plastic bearings and valves for pumps and axial-flow fans; machine parts, namely, cutting guides for machines in particular in the shape of chain and curve; machine parts, namely, plastic bearings and valves for construction machines; gear and drive wheels, track and guide rollers, all for machines and not land vehicles; bearing elements being machine parts, namely, bearing inserts, bearing housings; cutting guides for machines; machine parts, namely, mechanical seals; control discs being hydraulic controls for machines; bearing housings for machines; sliding and conveying elements in the nature of sliding bearings and conveyors, and plastic bearings for machines, namely, flange bearings, mounted bearings, thrust bearings, sleeve bearings, and spherical bearings; parts for engineering tools, namely, pipes, fitted for machines, for use in general mechanical engineering