Outfitters Score™
Excellent
Sig Sauer, Inc. scores as a top-tier build with fair pricing and a bare-bones configuration.
Our proprietary rating combines brand tier, price percentile within the caliber, feature completeness, barrel versatility, retailer availability, caliber practicality, and use-case fit.
Short Barrel: Verify Classification
This firearm has a barrel under 16 inches. It may be classified as an AR Pistol (with brace) or an SBR (with stock, NFA regulated). Check with the retailer to confirm classification before purchasing.
Description
The TREAD COIL sets a new standard in performance and value in the AR category. With installed accessories including ROMEO5 Red Dot Sight, Flat Blade Enhanced Trigger, and 13" lightweight handguard, the COIL is the perfect rifle package for the avid user or first-time buyer. Other features of the TREAD COIL include the precision 16" stainless barrel, ambidextrous controls, and 6-position Magpul SL Stock. Mfg: Sig Sauer, Inc.
Features
Ambidextrous|Ambi|Enhanced Trigger
Full Specifications
Overview
| Brand | Sig Sauer, Inc. |
| Model | RM400-16B-TRD-C |
| SKU | 100041053 |
| Rifle Type | semi auto |
| Platform | AR15 |
| Caliber | 5.56 NATO |
| UPC | 798681632381 |
Barrel
| Barrel Length | 13" |
| Barrel Finish | stainless |
| Barrel Profile | lightweight |
Receiver
| Forward Assist | No |
| Dust Cover | No |
Handguard
| Free Float | No |
Furniture
| Stock Type | collapsible |
| Stock Model | Magpul Sl |
Muzzle
| Suppressor Ready | No |
Sights & Optics
| Sights Included | red-dot |
| Optic Ready | No |
Compliance
| CA Compliant | No |
| Classification | Short Barrel: Verify Classification |
| NFA Item | Verify with retailer |
What's Included (Complete Rifle)
This is a complete, ready-to-shoot firearm.
Upper Receiver
Lower Receiver
Barrel
13"
Bolt Carrier Group
Handguard
Stock / BraceVerify with retailer
Grip
Trigger
Muzzle Device
Charging Handle
Gas Block
Gas Tube
Buffer Tube
Backup Iron Sights
Optic
Stock / Brace: Verify with retailer
We cannot confirm from available data whether this firearm includes a stock or brace. This distinction determines its legal classification.
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Manufacturer · Tier 1
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Build Guide
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State Check
This rifle has NFA or magazine considerations →
Swiss-origin firearms giant. The M400 and MCX platforms compete in the premium space, and Sig won the US Army NGSW rifle contract with the XM7.
View brand profile →M400 Tread Coil 5.56 Rome0 5 Red Dot - M400 Tread Coil 5.56 Romeo5 Red Dot
RM400-16B-TRD-C
Across 1 retailer
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