Set of 12 different rods ranging in density from 0.5 to 9 g/mL. Includes copper, brass, Pyrex®, rubber, acrylic, Tekaform®, aluminum, Delrin®, PVC, PTFE, poplar, and oak rods. Rods are 1/2" diam and vary in length from 1 1/2 to 2 1/2". A drilled, square block holds rods for convenient storage. Includes instructions. For testing Properties of Materials