Installed on Ibanez Artcore hollow-body.Obviously, I used the heads and washers from the stock set, because I like the appearance of the mixed metals.The high gear-ratio makes for excellent tuning stability. These would be decent tuners without the locks. The lock mechanism is simple and works perfectly.Some reviews mention the pin not sitting entirely flush with the tuner body. This is irrelevant once strings are in place, and I have not noticed any gaps at the tip of the pin where contact is made whatsoever.I have owned many high-end brand name tuners. With quality craftsmanship and materials, these are comparable to more expensive locking tuning machines.If your guitar has 10mm holes and a 45° angled screw in back, these will definitely work without any modifications.