Brake calipers house the brake pistons and pads, converting hydraulic pressure into mechanical force. These components are integral to disc brake systems on all four wheels of most modern vehicles. Calipers utilize one or more pistons to clamp brake pads against the rotor, creating friction and decelerating the vehicle. Construction typically includes a forged aluminum or cast iron body, incorporating bleed screws for air removal from the hydraulic system. Variations include floating, fixed, and multi-piston designs to accommodate diverse vehicle weights and performance requirements. Proper functionality relies on precise piston travel and consistent pad contact.