This is a violin adjuster screw made specifically for GOZ violins, crafted from natural stone. - Model Name: GOZ Violin Adjuster Screw AdjusTone Jem - Material: 10mm natural quartz (crystal) button cut Top: Swarovski crystal (colorless) V-cut Each one is carefully handcrafted. We support your performance by adding premium screws to your instrument! Please be very careful when replacing them. The instrument, tailpiece, and adjusters in the photos are not included with the product. #violin #バイオリン (violin) #ヴァイオリン (violin) #adjustone #swarovski #スワロフスキー (Swarovski) Thank you for viewing.