The 28146SW Brake Vacuum Switch Vacuum Pump Switch is a 12V electric brake booster component designed for automobiles. With a vacuum gauge purpose and a copper alloy contact material, this automatic operation switch features 3 screw terminals for easy mounting. The compact dimensions of 4.76x2.76x1.73 inches and a weight of 0.21 pounds make it a convenient and efficient addition to HVAC and refrigeration systems. The maximum and minimum switching voltages of 12.0 ensure reliable performance, making it a valuable tool for maintaining brake systems.