The Cannington RSL branch wants to contact the person who left a framed Vietnamese flag signed by veterans at its front door five weeks ago.
President Brett Caines said the club wants to put a memorial plaque under the flag to celebrate the 50th anniversary of the end of the war and explain the origin of the flag.
The flag was signed by members of the 101-field battery who served in Vietnam in 1966-67.
“It would be interesting if somebody could come forward and give some background to the flag,” he said.