This tuner is excellent value for money.
It is fully chromatic (yay) so suitable for pretty much any instrument.
As a clip on tuner, you just clip it to a part of your instrument that vibrates when a note is ringing and turn it on. Pluck a string (if you are using it for a stringed instrument), tune it to the desired pitch and you are good to go.
So far it has been accurate for drop-B, standard E on acoustic and electric guitar, drop D on electric and for concert tuning on a Ukulele.
The rotating part of the tuner came out of the box very stiff. When rotating it you really need two hands, else you will end up pulling the whole clip off the headstock and this is why I only gave four stars in quality and overall. I am sure it will loosen with time, but for now I need to remember to take two hands.
It looks awesome too, so plus points there!