AMP (now TE Connectivity) introduced the Mate-n-Lok connector in October 1963, which was similar to Molex's patented design but not compatible.

[1][2] First used in home appliances, other industries soon began designing it into their products from automobiles to vending machines to minicomputers.

Both were widely used in the computer industry and the term "Molex connector" is often used to refer to all nylon plugs and receptacles.

The first 5.25-inch floppy disk drive, the Shugart SA400, introduced in August 1976, used the AMP Mate-n-Lok connector part number 350211-1.

[6] The Molex 8981 series was only produced in a 4-position option, unlike the Mate-n-Lok family which includes many other contact arrangements.

Molex has since discontinued the 8981 series, but the original Mate-n-Lok connectors remain available from TE Connectivity.

Because the pins have a large contact surface area and fit tightly, these connectors are typically used for power.

Standard practice is to check for any sign of blackening or browning on the white plastic shell, which would indicate the need to replace the arcing connector.

Power delivery to these devices has increased in successive generations of PC components, as their higher signal sophistication and speed requirements have raised their electrical demands.