Made from either CNC Brass, Nylon or white ABS these set of 6 saddles are intended for a modern-day (post year 2000) Gibson USA-made or Armstrong Music-USA made ABR1 bridge. They will not fit the Nashville-style of Tune-O-Matic bridge or an original 50's or 60's ABR-1 that were fitted to a Kalamazoo-made Gibson guitar. These saddles do not have any notches for the strings to sit in and will need to be added once fitted to your instrument. Intonation screws not included but are also available from us.