I'm a bit embarrassed to say I bought these in error....... I was in air head mode this particular day, and believed I was ordering 3x3 for my Harley Benton CST24T. And even more dumb behaviour from me. when they arrived I started to set to work on the guitar and just before I was about to remove the first tuner......... Yep, I noticed my mistake. Sooo........... I have had these for quite some months, just sitting in my spares case. I didn't have an S type guitar in my collection at this time, but have since purchased a HB ST90 Swamp Ash (very nice, by the way). I have now installed these locking tuners on the the ST90. The original 'vintage' style tuners on the ST fitted a hole of 8mm diameter, so I had to ream them out to 10mm for the re-fit. This was not a problem, for me, as I have the equipment to do this (pillar drill, reaming tools etc) But if you haven't, please bare this in mind when ordering. Also bare in mind the neck will need removing from the body to do this work safely and correctly. I filled the old screw holes as, obviously the new ones didn't line up. And now I have a very, very smart and precise set of locking tuners. 19:1 ratio is spot on and gives excellent tuning. They feel very smooth and........ well... Expensive. Much more responsive and precise than the stock tuners on my Ibanez, Epiphone and other Harley bentons. There are no dead spots were your turning the tuner yet the string is unresponsive. Excellent set of tuners and the locking pins hold very well even on a plain unwound 00.9. A quick tip if you are going to undertake the work above and retro fit on 8mm holes: If you do not have proper reaming bit's, DON'T use a 10mm wood bit in your drill press. You will not be able to keep center as you remove the excess wood and will likely get a rip through on the cut. Maple is quite soft. Instead use a 9.92mm or 10mm drill bit for metal and drill, slowly to start with, from the headstock face through to the back, with everything lined up and clamped.