Eric writes about the Kayrank Helmet Rank System at The Gear Locker... "We have been following the Kayrank Helmet Rank System since SSD posted about their crowd funding project. That part of the project was not successful, but the company was able to create their rank system and, we at TGL were excited to see them in person.  We received 4 subdued rank inserts that can be used with the NVG mounting brackets."