Super smooth, super nice- A direct Drop-In replacement for the old Double Line Klusons found on mid 50's strats, but modernized with delrin bushings for backlash-free performance. These mount in 9mm holes, and you get a complete set of six with black bushings and screws. We've put these on a few Fender® Relics and they are awesome- look vintage, smooth as hell, hold tune like a ROCK! These have the vintage split shaft posts as well. We find these to be a superior machine to the far more expensive "branded" models, right down to the vintage correct ribbing and button shape- So why pay up $50 for a set of black tuning machines? The black plating is smooth and flawless, and they work better than any of the competitors..