Soft round head for soft playing. Designed for the Solo marimba performer, these mallets feature a large rubber core wrapped in 100% wool yarn for an enhanced, warm, full bodied sound. The Vic Firth American custom M1 Soft yarn marimba mallets have a soft round head for soft playing. The American custom keyboard mallets are designed to address a range of instruments and all dynamic levels. The yarn models feature a 3-ply nylon yarn that is virtually indestructible yet provides excellent cushioning for a softer sound. With birch shafts for rigidity and consistency, they are favored by players who prefer extra reach without the added flexibility of rattan.