37 Installation, maintenance, and repair of residential and commercial garage doors, high speed rollup doors, overhead doors, rollup doors, aircraft hangar doors, shutters, and door rollers; installation, maintenance, and repair of fire and security doors and door alarms; installation and maintenance of windows, doors, and screens; installation, maintenance, and repair of operable walls and curtains; installation, maintenance, and repair of driveway gates and gate operators; installation, maintenance, and repair of pet doors; installation, maintenance, and repair of commercial steel and aluminum entry doors; installation, maintenance, and repair of door openers and closers; installation, maintenance, and repair of loading dock equipment