Brake calipers are a crucial part of your braking system; many would say that it's the most important part on any vehicle or trailer. The brake caliper contains the brake pads and pistons. It fits like a clamp on a wheels rotor to stop the wheel from turning when the brakes are applied. Inside each caliper is a pair of metal plates known as brake pads. When you push the brake pedal, brake fluid creates pressure on pistons in the brake caliper, forcing the pads against both sides of the brake rotor, squeezing it and thus slowing the wheel. This caliper is coated in Dacromet, which is a coating that's often used in machinery for heavy trucks, wind turbines, boats, construction equipment and vehicles, and agricultural machinery. It has a smooth finish, and it can take a beating from salt water without suffering corrosion. It's perfect for your marine trailer, whether you're going into saltwater or freshwater.