This density rod set consists of twelve different materials ranging in density from 0.5g/ml to 9g/ml. The set includes copper, brass, polyoxymthylene-acetyl, rubber, acrylic, aluminum, polyformaldehyde-Tekaform, PTFE, PVC, oak wood, maple R3389wood, and glass. The rods are 12mm in diameter and range in length from 37mm to 60mm. Using this set, your students can explore mass, density, and volume. Measure the mass using a scale, calculate the volume using a graduated cylinder filled with water, and then calculate the density by dividing the mass by the volume.