Cympad's Undertones bass drum pack improves your bass drum's sound. The pack includes two bass drum spur Undertones and one bass drum pedal Undertone—cellular foam disks that decouple your bass drum from the floor, adding sustain and enhancing low end. You'll hear a fuller, richer tone from your bass drum. The proprietary non-skid material on the Undertones' underside anchors your drum set securely on any surface, reducing sliding and the need for drum rugs. Your bass drum spurs and pedals stay firmly in place during performances.