ProKussion 15 Key Soprano Glockenspiel with Wooden Resonating Chamber and Removable Keys (6 Extra Keys and 4 Beaters) The ProKussion Series Alto and Soprano Glockenspiel. Keys on the ProKussion Series Glockenspiel are all removable allowing the player to play in a variety of keys using the spares provided. The keys are also colour coded making it easy to learn tunes. Spare beaters are included. The 15 keys are positioned on a 4cm deep wooden resonating chamber which produces a bright, warm sound. A one page learning resource is included with instructions on how to play a number of well recognised tunes.