I have a great accessory for violin that is already selling $30k per year. I know it can do $250k / yr with some marketing investment.
GelRest Violin makes a range of gel pads designed to match the shape and color of typical violin chinrests. With easy peel-and-stick installation, our product is highly regarded by players and teachers for its ability to make the instrument much easier to hold, yet blend in with the look of the instrument. No other product has this combination of style and comfort, all at an affordable price. We think it is a "must have" for every violinist.