A 3-piston 65mm compressor head pump is the top part of a belt-driven air compressor. It uses three pistons, each with a 65mm bore (or diameter) to compress air. This multi-piston design allows for a higher volume of air to be compressed more efficiently compared to single or twin-piston models, making it suitable for more demanding applications. This type of pump head is typically paired with a powerful electric motor, often 3HP, and is used in a variety of industries, including automotive workshops, construction, and manufacturing, to power pneumatic tools and machinery.