The Economic Commission for Asia and the Far East (ECAFE) held its 14th session in Kuala Lumpur from March 5-15, 1958. This was a significant international event for newly independent Malaya. Special postage stamps (12 cents and 30 cents) were issued to commemorate it, featuring the UN symbol and the text "ECAFE Conference Kuala Lumpur, 1958."
This specific design is a known variant for these private FDCs. It likely incorporates the flag of Malaya (or a generic flag representing participating nations) and a globe symbol to represent the international nature of the ECAFE conference.
These FDCs were sent by registered mail, which adds to their collectibility and sometimes provides additional postal history value.