LP Vibra-Tone Standard Indigo Blue LP775-BL The LP Vibra-tone is a specially tuned aluminium tube which produces a bell like tone with amazing sustain. When the thumb covers the hole in the tube, a unique "wah-wah" sound is created. - Made of anodized aluminium - Open and close sound hole to create a "wah-wah" effect - Rubber Mallet Included.