Wak-a-Tube Pentatonic Scale Treble Octave SetA pack of 6 Wak a Tubes making up a pentatonic scale starting at middle C. Pitches included are: C40, D42, E44, G47, A49, and C52. Wak a Tubes are brightly coloured percussion instruments made from different lengths of plastic tubing. Theyre fun and easy for musicians of all ages to play simply whack them against a hard surface, hit them against each other, or lay them out on a flat surface and strike them with beaters. Playing Wak a Tubes in a group