Geissele Super Modular Rail Mk2
The Geissele Super Modular Rail Mk2 beefs up the original Mk1 handguard design using sliding backer nuts instead of threaded inserts to mount modular 1913 Picatinny rail sections. This makes one of the most robust handguard rail systems on the market even more bomber, but it does add a little more weight.
However, Geissele tells me they’ve actually shaved a few ounces by making some changes to the barrel nut as compared to the early versions of the Mk1. The could have gone without the internal slots for the backers, but anyone who’s installed a rail section with an uncaptured backer will tell you it is a pain in the ass.