Body shields are a piece of protective equipment worn around the torso for sparring or other training. They are made of foam or another type of padding surrounded by leather, this makes them durable and effective for absorbing the power of a punch. This allows the training boxer to throw body shots with their full power, or closer to it at least, while protecting the training partner. Breaking a rib is a large concern with taking body shots, whether in a bout or in training, and body shields help to mitigate that risk.
Body shields can also be paired with pads to further work on complex combinations. A major downside to sparring with a body shield is decreased movement. Many shifty boxers love to bob, weave, slip, and roll - all moves that require bending in the torso. Since wearing a body shield can feel like wearing a ski coat, it can restrict movement of the wearer greatly.