A set of 6 matt grey Stratocaster roller bridge saddles.
Roller saddles are great for improving tuning stability - they allow the string to roll over them on a low friction ball, minimising any of the string tension getting stuck behind a bridge saddle. If you're a common user of your tremolo arm, you're likely to have to retune your guitar regularly due to the tension of your guitar string fluctuating between the tension before the tremolo arm is used, and the tension after. As the tremolo arm is brought back to the original position, the tension tries to achieve equilibrium again by distributing itself equally over the length of the string. However, if there's a large amount of friction acting on it at the bridge saddles, this can stop the string from equalising itself.
With a roller saddle, the string is free to roll over the saddle. This minimises the unequal distribution of tension by allowing the string to slip over the saddle into the correct position. This removes one of the points where tuning instability can occur from (the other primary factors being the nut and tuning pegs (machine heads)).
These can be easily installed on any tremolo that accommodates the following dimensions -
Length - 22mm
Width - 10mm
Height - 5.5mm
String spacing - 54mm
Supplied with mounting screws, mounting springs, and height screws.