Product Overview
Now shipping with our new custom Torx T20 fasteners!
Sold Individually
XOS® in M-LOK - An evolution of our traditional G10 machined RailScales, XOS Scales are a 3-sided solution that offer twice as much grip surface in the same mounting footprint. Adding a 135º “wing” on each side of the panel allows for the XOS to tightly wrap your rail, and provides one seamless grip area for unparalleled handling and heat protection. CNC machined out of high quality US made Black FR4 or our brown terrian colored TerraCore (commonly known as G10), our scales provide an unmatched barrier against heat transfer. Available in four popular textures and varying lengths, these scales allow for multiple setups no matter how much rail space you have available. They will accommodate most popular handguard rail systems, however please check the specs below to insure these will fit yours.
TerraCore complements our line of Terra Bronze anodized and FDE polymer components as well as third-party branded tan anodized or Cerakoted rail forends. Unlike coating or painting options, our TerraCore scales are colored throughout and remain so after CNC machining operations. Offered in the same patented textures and resilient heat protection options you've come to expect. We are excited to introduce TerraCore XOS scales to our lineup.
Ships Free and Made in USA
- Quantity: Sold Individually
- Mount Type: M-LOK
- Footprint: 3-Slots, 4-Slots
- Width: 1.165"
- Thickness: 0.125"
- Length Dimensions: 3-Slot - 4.724", 4-Slot 6.300"
- Weight: 3-Slot - 0.64oz, 4-Slot - 0.82oz (w/ hardware)
- Material: FR4
- Color: Black FR4®, TerraCore®
- Hardware: US Made 416 Stainless M-LOK Nuts
- Fastener: US Made T20 Torx Fasteners w/ Nylon Thread Patch
Fitment Info: Fits rails with mounting flats of 0.678" or narrower including the following:
- AAC Teardrop
- ADM MLOK
- BCM KMR/MCMR
- Bootleg Inc. CamLok
- CMMG KeyMod/MLOK
- Dakota Tactical HK Series KeyMod/MLOK
- Daniel Defense Slim
- Daniel Defense MFR MLOK - DOES NOT fit the MFR XL Rail.
- Fortis Night Rail
- Geissele 4-Sided Rails (Mk4*, Mk8)
- Geissele MK16 (URG-I)
- HK USA MR556 A4 M-LOK Rail - Only fits at 6 o'clock, DOES NOT fit at 3 or 9 o'clock.
- HK Parts HK Rails
- Hodge/FN Wedgelock
- LMT MRP-L MLOK
- Midwest SSK/SSM
- Midwest G3KL/G3ML
- Midwest Gen 2 Extended AK MLOK
- Parker Mountain Machine Scar Bottom Rail
- PWS Mod 1/Mod 2
- Sig Sauer Canebrake SD
- Sig Sauer MCX-SPEAR LT - Only fits at 6 o'clock, DOES NOT fit at 3 or 9 o'clock.
- Sig Sauer MCX-SURG SD Rail - Only fits at 3 & 9 o'clock positions, DOES NOT fit at 6 o'clock position.
- Sig Sauer MCX-SURG Low-Profile Rail - Only fits at 6 o'clock, DOES NOT fit at 3 or 9 o'clock.
- Sig Sauer MCX Virtus SD
- SLR AK ION
- Vltor Freedom
Does not fit:
- Brownells BRN-180
- Black Rain Ordnance MLOK
- CZ BREN 805
- Daniel Defense RIS III
- Geissele MK18 MLOK
- KAC URX 4 KeyMod/MLOK
- KDG MREX SCAR Rails
- Larue 2.0 Stealth MLOK
- Noveske NSR, NHR, NSRM
- Radian Model 1
- Radical Firearms MLOK
- Sig Sauer M400 MLOK/Tread
- Sig Sauer M400 X-Series SDI
- Sig Sauer MCX Rattler Non-SD
- Sig Sauer MCX-SPEAR (308)
- Sig Sauer MCX-SPEAR LT SD Rail
- Sig Sauer MCX Virtus Non-SD
- Sig Sauer MPX Factory 4" & 8" MLOK Rail
- SMOS Arms GFY MLOK
- SOLGW Wedge Lock MLOK
- SOLGW M89/L89 MLOK
- TriArc TriLok MLOK
© 2025 RailScales, LLC. All Rights Reserved. RailScales®, XOS®, XOS-H®, Black FR4®, TerraCore®, Terra Bronze® are registered trademarks of RailScales LLC.
For all patents and trademarks, see www.railscalesip.com
