Washboard instrument

It was July the 1st 2017, at Canada’s 150th National Day event.  A music instrument aroused my interest. It looked like a washboard. If you look closely, it is actually a washboard. After searching online, I found that it was really a washboard，a kind of percussion, as it has no resonance box  nor wire, is probably used to create some scratching sound effects, should wear out finger nails pretty good I guess.

price ranging from under 100$ to several hundred dollars