AcoustaGrip Shoulder Rests are a unique solution for every violinist. AcoustaGrip gives you the securest grip of any shoulder rest without discomfort and rigidity, allowing you the freedom to move and adjust. Long practice sessions can be a joy. You can focus all of your attention on honing your technique and playing more expressively. No more constant physical pain that all too often accompanies playing with a hard, rigid shoulder rest.