The ATI AR-15 X2 Scorpion Recoil Pistol Grip will not fit your Scar 17 without modification to your Scar's grip tang. Tangodown makes a grip that will work with your Scar without modification. You can find that grip using the following link:
https://www.opticsplanet.com/tangodown-ar-rifles-reduced-angle-form-battlegrip-grip.html