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Sig Sauer
M400
$1,899.99
$1,749.99
Sale Price
Available
California Restriction Notice
This item is restricted for standard California customers and may not be transferable in California without a qualifying exemption.
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Sig Sauer M400 SDI Sentry, Semi-automatic Rifle, AR, 223 Remington/5.56 NATO, 16" Threaded Barrel, Anodized Finish, Black, 30 Rounds, 1 Magazine, Includes ROMEO 5 Red Dot and Foxtrot MSR Light RM400-SDI-16B-R5FX
Key Details
Brand
Sig Sauer
Manufacturer Part Number
RM400-SDI-16B-R5FX
UPC
798681716128
SKU
SGRM400-SDI-16B-R5FX
Current Stock
86 available
Quantity Updated
Sep 6, 2026 5:15 AM
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Purchase Requirements
- This product requires FFL processing before pickup or transfer.
- Age verification is required before checkout completion.
- California compliance or distributor restriction review may apply.
- Final availability is confirmed at checkout.
In-Store Pickup Required: All firearm purchases must be picked up at our Beverly Hills location after background check completion.
Product Description
The M400-SENTRY offers a ready-to-go solution for the most discerning shooters, combining the proven capabilities of the M400-SDI X platform with the multi-purpose functionality of the ROMEO5 GENII red dot, FOXTROT-MSR Full Size Light and a vertical foregrip. This combination of standardized features makes the M400-SENTRY an out-of-the-box solution for home/personal defense, advanced training or recreational shooting.
Features
- ROMEO5 GENII Red Dot, FOXTROT-MSR Full Size Light
- Vertical Foregrip
- Fully Ambidextrous Controls (Safety, Charging Handle, Bolt Catch & Release)
- Free-Floating M-LOK Forend
- (3) M-LOK Rail Covers Included
- SIG 2-Stage Matchlite Duo Trigger
- 16 Chrome/Moly Steel"
- Barrel with 1:7 Twist Rate
- 6-Position Magpul MOE-SL Stock
- Low Profile Gas Block with Mid-Length Operating System
Specifications
UPC:
798681716128
Manufacturer:
Sig Sauer
Manufacturer Part #:
RM400-SDI-16B-R5FX
Model:
M400
Model (Alt):
SDI
Action:
Semi-automatic
Barrel Length:
16"
Capacity:
30 Rounds
Finish:
Anodized
Grips:
Polymer
Type:
AR
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