This model is LECO, LECO is used same way as LORA.
Model fixes the issue of bad hair over one eye / both eyes.
With weight 1-2.5 you will get hair over one eye, it depends on several factors like model and how long your prompt is how much weight you have to use.
With weight of 3-4+ you usually get hair over both of your eyes. Test around the weight. Weight can go to +7 and have decent image. More weight changes the composition and might give random effects like double colored hair and stuff.
It can slightly alter composition.
With negative weight the image is really random. Very often food is involved in some strange way.