6" & 7" Bongo. The birch body is made of cowhide leather for a genuine play and a firm and crisp sound. Adopts a tuning system with the included wrench, and it can be pinched up and down for tighter tuning. Hardware colors are trendy black powder coated black for a professional look. You can also use the BGS-1 (sold separately), and you can also enjoy playing with the knees.