The Bao Gong is very different from other Chinese gongs in that it features a raised boss, or nipple, in the center. For this reason they are often referred to as nipple gongs. Bao Gongs have a very clear and beautiful tone without much of the shimmer found in other gongs. In fact they have more of a bell sound with a distinctive pitch while still producing subtle harmonic overtones. They are available in a range of sizes with smaller ones having a higher pitch and larger ones having a deeper pitch.