Basically stock

[Packard]

I was reading a magazine article and they quoted Glock as saying that Jessica Abbate shot a model 24 that was "basically stock".

What modifications would they do that they could still call the weapon "basically stock"?

(The model 24 is a 9mm Glock with a 6 inch barrel and a longer slide. It is available from their catalog; it is longer in the slide than a model 1911 giving it an improved sight radius.)