This Hollyland spare (part PS-XLR4P-EU) is a power supply with a 4-pin XLR DC output and an EU-type mains plug, used to power the base stations of Hollyland's professional wireless intercom systems. The supplier lists it for the Syscom 1000T and Mars T1000. Hollyland's Syscom 1000T base station has a 4-pin XLR male DC input accepting 10-20 V DC, and the Mars T1000 base station is powered from an AC adapter with a 4-pin XLR connector (its DC input accepts 7-36 V). These full-duplex intercom systems are used by film crews, broadcast and live-event teams, churches and theatre productions to keep directors, camera operators and crew in constant communication, so a spare or replacement base-station supply is important for rental companies and for productions that cannot afford downtime from a lost or damaged adapter. The locking 4-pin XLR connection is the standard used on broadcast and cinema equipment and resists being pulled out accidentally. Note that this is the EU-plug version: a South African user would need a suitable plug adapter for local wall sockets. The intercom equipment itself is not included.