Nanae Mimura Series mallets are slightly heavier than NZ Series mallets. They feature rubber disk cores hand wrapped with latex, and are covered by North American wool. Encore's unique hand wrapped latex process enhances the fundamental allowing harder mallets which do not sound harsh, and improves the feel of the mallet's rebound. The yarn is all natural wool which is not chemically processed and therefore particularly soft and durable. (Our yarn is purchased from the sheep farm that harvests the wool - the yarn is so natural that you may occasionally see a small piece of hay from a mallet head!) The softness of their yarn combined with the hardness and clarity of their latex-wrapped disk cores make NM Series mallets two-toned and very versatile. Very soft, with birch shafts.