A power cage, also known as a power rack or squat rack, is a popular piece of weight training equipment that is mainly used as a rack for freeweight barbell exercises. Unlike a Smith machine or any weight machines, it doesn't impose movement restrictions. The bar holders can be adjusted to any height on the rack, so that you can set the bar at various heights depending on the height you need to unrack the bar at for exercise you're performing. The safety bars are the longer bars extending the entire depth of the rack and are set to a position just under the bottom of your range of motion, to catch the bar in case your strength gives out.
These squat racks for sale are also used for bench presses and a variety of other pressing and pulling exercises. They are also called power cages. While old style squat racks have fixed-height safety bars that are about the right height for some users, but not others, and only for one exercise, the modern squat racks for sale here are completely adjustable.
Depending on the height of your bench, you'll likely want to set the safety bars a little lower than you would for squats. You'll figure it out. The idea is to set the sefety bars just a little lower than the bottom of your range of motion so that it will catch the barbell if you fail a rep. It increases of the safety of bench pressing, squatting, and other presses such as shoulder presses and incline presses. These racks are also used for rack pulls, a deadlift-like exercise with a shorter range of motion and heavier weight.
Most power racks include a pull up bar. Some power racks also include other optional attachments such as a lat pulldown machine. Over the years, people have come up with many exercises that can be performed in a power rack with additional pieces of equipment, such as dips and sit-ups.