The Sonor Palisono Diatonic Tenor-Alto Xylophone uses bars made of a specially developed fiberglass material. The sound characteristics are similar to rosewood. The uniform structure of the xylophone bar material is superior to rosewood and does not readily absorb moisture, the cause of intonation problems. Palisono bars are heavier than rosewood and therefore rebound less when struck sharply. Sonor Diatonic Xylophones include all F#s, Bbs, and a pair of mallets.