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This product can expose you to chemicals including lead, known to cause cancer and birth defects. For more info visit P65Warnings.ca.gov.
Sig Sauer
M400
$1,649.99
$1,499.99
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 XSERIES, Semi-automatic Rifle, AR, 223 Remington/5.56 NATO, 16" Carbon Steel Barrel, Anodized Finish, Black, Magpul SL Stock, SIG Flatblade Match Trigger Low Profile Gas Block With Mid-Length System, 30 Rounds, 1 Magazine RM400-SDI-16B-P
Key Details
Brand
Sig Sauer
Manufacturer Part Number
RM400-SDI-16B-P
UPC
798681664634
SKU
SGRM400-SDI-16B-P
Current Stock
16 available
Quantity Updated
Sep 6, 2026 5:53 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 SDI X Series is the out of the box performance solution. The X Series features a 16" chrome molly barrel with a free-floating M-LOK handguard, SIG Flatblade Match Trigger, ambidextrous bolt catch and release, Magpul SL stock, and mid-length gas system.
Features
- Ambidextrous Bolt Catch and Release
- Low Profile Gas Block with Mid-Length System
- SIG Flatblade Match Trigger
- Hybrid Compensator/Flash Hider
- Magpul SL Stock
Specifications
UPC:
798681664634
Manufacturer:
Sig Sauer
Manufacturer Part #:
RM400-SDI-16B-P
Model:
M400
Model (Alt):
XSERIES
Action:
Semi-automatic
Barrel Length:
16"
Capacity:
30 Rounds
Finish:
Anodized
Grips:
Polymer
Type:
AR
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