37 Building construction; repair, namely, repair and maintenance of chemical, manufacturing, electric, and nuclear power plants, machinery and machine tools; installation services, namely, installation of technical works in the nature of equipment used for automated industrial operations, machines and machine tools; repair and maintenance of machines and machine tools for treatment of materials, metal treating and production, motors and engines not for land vehicles, machine coupling and transmission components not for land vehicles, agricultural implements other than hand-operated, automatic vending machines, generators of electricity, nitrogen generators, and parts and fittings for the aforesaid goods; repair and maintenance of rail systems for lifting and transporting devices, pipe plugs for forming gas welding and for oxygen measurement, welding seals, rivets of metal, sockets and push-on bits for screwdrivers, pneumatic and electric tools, impact wrenches, screwdrivers, pulse-type screwdrivers, camera and scanner screwdrivers, drilling, grinding and riveting machines, and parts and fittings for the aforesaid goods; repair and maintenance relating to blind rivet guns, torque wrenches, machines and installations for the automated screwing together of parts, multi-spindle, wheel, coupling and connecting rod screwdrivers, pneumatic hoists, chain hoists, winding spools for flexible hoses, dust extraction devices, devices for producing nitrogen, devices for producing oxygen-rich air in the nature of oxygen generators, and parts and fittings for the aforesaid goods; repair and maintenance of pumps for liquids and/or gases, centrifugal and double membrane pumps, milling machines, electropneumatic electrode cap milling cutters, milling apparatus for pipe ends, pipe cold cutting machines, and parts and fittings for the aforesaid goods; repair and maintenance of hand-operated tools and implements, hand-operated pipe and pipe working tools, hand-operated assembly tools, handheld pneumatic tools, and parts and fittings for the aforesaid goods; repair and maintenance of handheld calibration tools, handheld impact wrenches and hand-operated screwdrivers, torque and click-type wrenches, hoists, winding spools for flexible hoses, carriage systems for lifting and moving machinery, swivel arms, handheld milling cutters, handheld electropneumatic electrode cap milling cutters, external and internal centering devices for pipeline construction, tensioning devices for pipes, pipe clip tensioners, centering devices for pipes, pipe centering chains, and parts and fittings for the aforesaid goods; rental of hand and power tools, metal-working and metal-treating machines, and machine tools, namely, wrenches, drills; rental of technical apparatus and installations, namely, oil well drilling tools, construction machines and apparatus; industrial machine tool maintenance