As you might have guessed from their name, press-fit connectors are pressed through properly dimensioned plated-through holes on a printed circuit board (PCB). Press-fit pins forge a solid bond between two parts that requires no additional soldering. Frictional force holds the parts together after they have been joined to create a gas-tight, cold-welded, solder-less connection.

This technology is an alternative to the soldering method and offers a number of advantages over its more traditional counterpart. With press-fit connectors, you can eliminate a number of negative aspects that come along with soldering: thermal stress on the PCB, cold solder joints, shorts (caused by solder bridging), and the elimination of lead-free solder, which introduces its own set of problems. Press-fit connectors are also easily repaired, more environmentally friendly, and cost effective.

Press-fit pins emerged in the early 1970s. The DIN 41611-5 standard for this technology was first published in 1984, and the IEC guidance 60352-5, "Solder-less connections – Part 5: Press-in connections – General requirements, test methods and practical guidance” soon followed. Components that meet these qualifications are called 'compliant,' and the term 'compliant pin' is widely used throughout the market.

Engineers started replacing soldered pins and screws with these alternatives in the mid-1980s, and modules equipped with these pins debuted in 2005.

Press-fit technology allows manufacturers to avoid soldering when assembling PCB electronics. The press-fit connection is formed when a pin is pressed into a fitted, plated-through hole in a PCB.