Is a square D breaker allowed in a general electric panel box ??
I always call it out. When you open the panel there is typically a legend in there stating exactly what breakers can be used. This box is tested and given a blessing from the UL (Underwriters Labratory) and it is intended to be used as tested. Mix matching breakers is not allowed according to the sticker within the panel itself.
No. It will tell you inside panel