FAST SF Helmet with Factory RAILINK Power & Data Rails

The RAILINK-Enabled FAST SF is the new-generation Ops-Core flagship with the RAILINK Power and Data ARC Rail system factory-installed. Gentex unveiled RAILINK in June 2025 as the first production powered rail system for tactical helmets. Instead of running individual CR123 or AA cells in every device, the helmet has a single Battery Pack+ that feeds power and data through the rails to compatible accessories.

The system auto-selects voltage: 3V or 9V for NVGs (PVS-31A, BNVD-1531, GPNVG-18, Kestrel), and 13V for accessory nodes. Compatible accessories at launch include the Princeton Tec Switch MPLS in a RAILINK variant, the SureFire HL2-A white/IR light, and the CORE Survival HEL-STAR Rail Strobe. Gentex has also signed development partnerships with MOHOC, AMAD, NanoAi, and seven other licensees, so the accessory ecosystem will keep expanding.

RAILINK adds approximately 8 oz (226 g) of rails and hotshoe weight versus the bare FAST SF, plus the Battery Pack+ on the rear of the helmet (which doubles as a counterweight, reducing the need for a separate counterweight kit). Lead times are 90 days from Gentex. This is the right buy if you are kitting out a new high-end build and want to consolidate batteries and cables, not the right buy if you already own a working FAST SF and a stack of accessories on standard ARC rails.