This is an L-shaped adjuster for a violin. SWAROVSKI (Capri Blue) is attached to the surface. It sparkles very vividly and beautifully. The screw itself is a general-purpose M2 size, so it can also be used with other L-shaped adjusters such as Wittner. If you want multiple pieces or other colors (see photo 6), please consult in the comments. Wittner Adjuster Violin Viola A-string E-string Swarovski