Tail Gut
Tail Gut is made of beef gut (bovine serosa) used to attach the tailpiece onto the instruments of the violin family and some viols.
Tail Gut is usually sold by a diameter thickness. Violins and violas use tail gut that is from 1.90mm to 2.20mm thick. Cellos use a gut around 3.00mm thick, and a violone / double bass should use a gut of about 5.00mm thick.
The thickness that you choose depends on the qualities you are looking for. A thicker gut will be more stable and stretch less than a thinner gut, but it may not allow as much vibration in the tailpiece as the instrument needs to sound its best. One of the advantages to the use of real gut over synthetic gut is that the flexibility of the tail gut can be changed simply by changing the diameter of the gut, and this can have a radical effect on the tone and response of the instrument.
