Amazon Customer 5.0 out of 5 stars Great product, as advertised November 28, 2018 Colour: BlackV3Verified PurchaseUsing this product on my Ibanez Artcore AFS75T with a Bigsby tremolo, it really does keep my middle strings in tune. Highly recommended, well worth the money. Great for any Gibson style headstock! Even my Luthier was impressed with how well it works.