It might not have been her usual fashion accessory, but it was the perfect prop for a rendition of classic tune YMCA.
The fun-loving model gave a hilarious rendition of the Village People number at a charity karaoke night, joined by star pals including Tom Hanks.
The Forest Gump actor lent his vocals and helped recreate the song's iconic video – which features a police officer, construction worker, Native American, a biker, a serviceman, and a cowboy.
He donned a yellow hard hat, and was at once point seen wrestling Heidi for the microphone.
The pair joined a host of famous faces, including expectant actress Molly Simms, Desperate Housewives star Kyle MacLachlan and actress Kristen Bell.
They were using their vocal talents to raise funds for UNICEF.