Pretty much a necessity imo - Magpul Industries SL Grip Modules & HK Polymer Trigger Housings

Almost a requirement for those with smaller hands. Throwing the safety selector on my PTR91 meant i had to break my grip every time in order to do it which was annoying.

This paired with the grip module completely transforms these guns into the 21 century. Unless youre going for a retro vibe, these are a must have upgrade imo.