Grips should be installed by a qualified gunsmith.
They are not intended to be "drop in" ready for installation.
Work may be required to fit to your pistol.
Raw aluminum grips should be anodized for surface hardness and wear resistance. Other coatings may be applied over the anodizing.
Modification of your firearm may void the manufacturers warranty.
BUL pistols require a conversion to use grip bushings in order to fit our grips.