Pitch-Key Drop Tuning System for Guitars

This is a great tool for enabling instant drop D on your strat without having to cut into the wood or having to replace any hardware. It sits behind the nut and works by putting extra tension on the string or releasing it again.
Downside: it is a bit of a hassle to properly get it on the strings and you have to re-do this every time you change strings.
Upside: It doesn't come off accidentally in my experience. It works flawlessly every time.

It works very well with LP. No problems there.
With my PRS SE24 I can't use it. That was expected as in normal (manual tuning) cases when I drop lowe E to D I need to retune other strings as well. It's probably due to bridge design (or setup).
Hint: Before you decide to buy this, chek that other strings will stay in tune when you lower the 6'th E string.

Quite handy thing. You can fast and easy drop your tuning during play. Good thing for begginers. More advanced players not necessarily need this thing. Easy mounting and using. Best matching with headstocks with strings going straight without angle.

great little tool for changing the tuning at no time. it doesnt looses pitch and for the money is a must have

Using it to frequently switch between standard and drop D

Positives
- works well and keeps the ratio pretty well so once set up haven't had a need to re-tune
- easy mechanical operation

Negatives
- Due to lack of gears a bit stiff so needs to have some force and leverage to turn which makes changing tuning mid-song a bit awkward and difficult unlike a detuner