FIXER's Gold Tailpiece Lock System for inch-sized tailpieces. FIXER's feature is that by simply replacing the original studs, without changing the appearance, the tailpiece's performance is 100% maximized, and sustain is improved. Other benefits include improved string vibration transmission, making the body resonate like an old guitar. The instability of the string ends is eliminated, and tuning becomes stable. Many advantages, such as preventing body damage from tailpiece dropping during string changes, are available. The material is iron for both the studs and the base spacers. You can tighten the studs to increase sustain according to the music style, loosen them to create an original sound, tighten only the high-E string side for high-frequency emphasis, tighten only the low-E string side for low-frequency emphasis, and so on, allowing you to create various sounds with a single guitar. A set of studs (2 pieces) is included. Base spacers, a total of 3 sets (6 pieces), 2.5mm, 4mm, and 5.5mm for height adjustment, are included. The condition is almost new, as it has been used for about 2 hours after being purchased new. The current price when purchasing new is 3,520 yen. Especially recommended for GIBSON USA (including CUSTOMSHOP). Thank you for your consideration.