Created to be nearly the same size as the rubber spring mute that comes standard on the Ibanez AZ series. *Please note that these are handmade, so there may be variations in size. The third photo shows the original part that comes with the AZ. It suppresses the resonance/vibration of the springs. Raw Vintage and other soft-type springs can sometimes produce too much reverb, but using this will help to moderately suppress the sound. This is a set of 5, so you can adjust the number of mutes to change the sound. The original part is made of rubber, but this is made of silicone, considering aging and deterioration. Ships via mini-letter. 2TRX5BA010 2TRX5BA011