These are adjuster screws for cello tailpieces. Beautiful rhinestones are used on the top of the screws, and green crystal glass is set on the base. Each one is carefully finished by hand. The rhinestones on top sparkle brilliantly. The sharply cut base is designed in a button shape for easy turning. Type: Cello Accessories/Parts: Other Product Name: Adjustone Gem (Set of 4 Cello Adjuster Screws) Top: Swarovski (Colorado Light Topaz) V-cut Base: Crystal Glass (Emerald Green) 10mm Button Cut Screw Diameter: M3 Confirmed to fit most cello tailpieces (Bovard & Monnier, Bogaro & Clemente, Accuacoustic, Wittner, etc.) We support your performance by adding premium screws to your instrument. Please be careful when replacing the screws. This product does not include the instrument or tailpiece. #Cello #adjustone