This weight mounts in the lower pocket of the MDT SRS-X Elite, SRS-X Lite & SRS-XF Premier buttstocks. The weight and its hardware will add 0.65 lb to your rifle system all the way at the rear, moving your balance point rearward significantly. To install, simply remove the buttpad assembly, slide the weight into the lower pocket, attach with included screws and reinstall the buttpad assembly.