GHS created Fast Fret more than 30 years ago.
This product is a guitar-string cleaner that is said to make strings last longer, sound brighter, and feel slicker.
It has become a true best-seller among guitar accessories.

More recently, D'Addario released a competitor to Fast Fret: XLR8.

The concept of both products is very similar: a product-soaked pad in a metal tin (Fast Fret used to come in a plastic case and is now in metal). The metal tins seal well so the applicator does not dry out.
One thing is certain: cleaning your strings after playing helps them last longer.
We tested two guitars: one cleaned with Fast Fret after every session, and one left untouched after each session.
After two weeks the difference is clear: the “Fast Fret” guitar has bright, shiny strings, while the other is starting to oxidize.
To the touch, the slick feel of strings treated with Fast Fret (or XLR8) makes playing easier, and when recording, finger squeaks disappear.
Oxidation is the enemy of tone. Fast Fret protects but is not a rust remover — it will not revive damaged strings. While it extends the life of a set, the strings still lose elasticity over time, so tone quality declines as they age.
Verdict: Fast Fret makes playing easier and helps your strings last longer (as long as you start treating them as soon as you put on a fresh set). But remember: the most important step against oxidation is cleaning your strings after you play (with a cloth, Fast Fret, or XLR8 — your call!).