With my grip I tend to apply just enough pressure to keep th slide from locking to the rear on an empty mag. It is a slide stop, not a slide release.

I keep several of these as a Glock Armorer. It is definitely a great addition.

Makes releasing the slide a no brainer.

a must have much easier to manipulate that the factory one

A must have. This is very cheap and inexpensive addition to the pistol. Makes letting the side go forward so much easier, especially if you use gloves.

Comes in very handy for people with stubby little thumbs like mine.

I have one on a 26 and a 21. They're great for faster mag changes. However, if you have big hands then be careful of your thumbs causing slide lock when you don't want it. Ironically, I've never had any issues with that with the 26, but I did once during a competition with the 21.

I have one on my G-21 and love it.

must need for any glock