This set comprises 12 hardwood triangular prisms with 6 pairs identifiable by matching, colored musical notes and a unique sound when shaken. Prisms are 2"L x 2.4"H x 2.4"D. • Musical blocks help with personal development. Sensory play with these fun, wooden blocks can assist with language development, problem solving and motor skills. • Help children develop their listening skills. A colored musical note only appears on one side of the prisms so they can be turned upside-down to test discriminatory skills. • Constructed with hardwood, these blocks have a smooth, warm feel, rounded edges and can be used indoors or outdoors. • Helps learners in their sensory development and understanding of the world through sound.