what is steel locker?

Steel Lockers are a security device.

Plain and simple, Steel lockers are an old-fashioned security device. Indeed, the name locker tells you what the locker does. A Steel locker is made to LOCK something up. Without a doubt, most people have seen or used a locker before. Some of the places we see lockers are: schools, gyms, health clubs, mailrooms, breakrooms, locker rooms, fire departments, military bases, bus or train stations, airports, and countless other locations.