The Soloist Series IP400 extra hard yarn marimba mallets bring together quality material and construction you can rely on to help perfect your playing. The 100% wool yarn creates pleasant tones in the low ranges of marimbas. The yarn, wrapped around a hard rubber core, makes the IP400 resonate sweetly with a warm fundamental tone. Polished birch handles put the control firmly in your hands. The same care and precision you put into music preparation is used for crafting the Innovative Percussion Soloist Series mallets.