Shoulder rests
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Kun is the standard of shoulder rests. Most shoulder rests fit a couple of sizes so that it can grow with you. They come in all sizes from 1/16-1/4, 1/2-3/4, and full size (4/4). If you have a shaped case or just one that is a little small, try the shoulder rest with collapsible feet.
The shoulder rests of all shoulder rests is the BonMusica. This isn’t for everyone but for those with longer necks or tension issues this shoulder rest is a game changer! I personally have used this one for over 10 years and I recommend it all of the time. Although it does come in smaller sizes, because of the price commitment I don’t typically suggest it for those not yet in their full size instrument. Everything about it is fully customizable. There are extra long feet screws and the whole padded area bends and moves to mould to your shoulder.