These 3 and 4 pin DC plugs are now commonly used for multi-output low voltage power supplies. They have a similar appearance to Mini-DIN plugs but have larger diameter pins which are capable of carrying greater current. Locking and locking plug variants are available. They can usually be identified by an engraved arrow symbol on the back-shell of the plug. The 3-pin plug will not mate with a 4 pin jack (and vice versa).
|3-Pin and 4-Pin DC Plug|