Genuine HAUS extended castle nut HK416 A5 style.
These castle nuts are machined from 4140 chrome-moly steel bar stock then receive a hot black oxide treatment to inhibit rust and give them a shiny black finish.
Proudly made in Texas, exclusively for HAUS MANUFACTURING LLC.
* These castle nuts are compatible with the HK MR556 receiver extension (mil spec) as well as the newer style commercial receiver extension used on the HK416 A5/A7/A8 rifles, they are NOT compatible with the older style commercial receiver extensions found on the HK416 A3 rifles.
🇺🇸 Made In USA.