From Wikipedia
Suzu (鈴) are round, hollow Japanese Shinto bells that contain pellets that sound when agitated. They are somewhat like a jingle bell in form, though the materials produce a coarse, rolling sound. Suzu come in many sizes, ranging from tiny ones on good luck charms (called omamori (お守り)) to large ones at shrine entrances. Suzu are, however, classified as small bells, since big bells are referred to as kane. The former is associated with Shinto and shrines while the latter is related to Buddhist temples and ceremonies.