Sig Sauer Laser Engraved Grip Module, Fits Sig Sauer P320F 9/40, Tungsten Infused Polymer, Medium, Gray 8901005 The LTXG Grip Module uses a tungsten-infused polymer that is then molded into the part. This patent-pending process results in a grip module that has the weight of steel and the flex of polymer. We've taken this a step further and laser-stippled the grip module for a more aggressive gripping surface. Install your P320 Fire Control Unit into the LTXG" and you'll have one of the flattest" softest shooting pistols on the range.