A vest frottoir or rubboard is a percussion instrument used in zydeco music. It is usually made from pressed, corrugated stainless steel and is worn over the shoulders.
It is played as a rhythm instrument by stroking either bottle openers or spoons down it. Many of these instruments are home-made, but Don Landry of Louisiana is a renowned maker of frottoirs – or rub-boards as they are also known – making them for Clifton Chenier's band and Elvis Fontenot and the Sugar Bees, amongst others.