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Stern Defense SD 16.1in MOD4 MLOK .40SW Upper Receiver Assembly 15in M-LOK Handguard .578-28 TPI 1-16 Twist Rate Black 015SD15INMD4ML16.1INBR40SWKK

Stern Defense SD 16.1in MOD4 MLOK .40SW Upper Receiver Assembly 15in M-LOK Handguard .578-28 TPI 1-16 Twist Rate Black 015SD15INMD4ML16.1INBR40SWKK

Stern Defense · Upper Receiver

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Best price

$600.00at OpticsPlanet

Out of stock Sale checked Oct 23, 2026

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OpticsPlanet $600.00Salechecked Oct 23, 2026 Out of stock Buy at OpticsPlanet

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Price history

Lowest in-stock price in the last 30 days: $600.00 at OpticsPlanet. Dashed line = out of stock. Tracking since Oct 12, 2026.

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OpticsPlanet$600.00$600.00$600.00

Since Oct 12, 2026.

About this part

The Stern Defense SD 16.1in MOD4 MLOK .40SW Upper Receiver Assembly 15in M-LOK Handguard .578-28 TPI 1-16 Twist Rate Black 015SD15INMD4ML16.1INBR40SWKK is a 16.1" upper receiver from Stern Defense. One store lists it, OpticsPlanet at $600.00. The lowest in-stock price in the last 30 days was $600.00 at OpticsPlanet.

Fits and works with

Muzzle thread
.578x28 · Muzzle devices
Barrel length
16.1" · Handguards
Handguard length
16.1" · Barrels

Specifications

Manufacturer
Stern Defense
Color
Black

From the manufacturer

Stern Defense SD 16.1in MOD4 MLOK .40SW Upper Receiver Assembly 15in M-LOK Handguard .578-28 TPI 1-16 Twist Rate Black 015SD15INMD4ML16.1INBR40SWKK. The free float M-LOKhandguard from Stern Defense offers excellent ergonomics while remaining lightweight and strong. This handguard is M-LOKcompatible to accept your favorite attachments. Features a secure clamp on mounting system that ensures that the handguard remains in place even under heavy abuse sustained full auto fire and shooting prone from a bi-pod. Machined from 6061 aircraft grade aluminum and hard-coat anodized for longevity and durability. These handguards also feature quick disconnect swivel holes. Barrel. Stern .40S&W barrels are ideal for gun lovers who want to build their own custom dedicated .40S&W AR15 upper group. Machined to tight tolerances with quality as a top priority you can't go wrong with the SD .40 cal barrel. Receiver. Mil-Spec flat top upper receiver with Stern Defense laser engraved dust cover and forward assist. Machined from 7075-t6 aluminum and hard-coat anodized. Mil-spec dry film lube in the bore. Charging Handle. Mil-spec charge handle for AR-15 rifles. Laser engraved with Stern Defense logo. Their latch is Ergonomically designed and provides a positive grip and easy one hand manipulations while charging your weapon under stressful situations. Made from 6061 aircraft grade aluminum billet and hardcoat anodized. Bolt.. Made with 8620 AISI steel and boasting a Mag-Phosphate finish the Stern bolt fits into Mil-Spec and Glock-pattern upper receivers. It functions with Colt SMG Glock magazines and it's fully compatible with standard AR15/M16 charging handles. Comes fully assembled with all sub-components installed including firing pin/spring/retaining pin extractor and extractor spring. Also included in bolt assembly is a propriety center and roll pins. Their 40SW bolts incorporate their new bolt design which caters to single stage triggers with short resets. It also allows use with the JP silent capture spring but is not recommend for 40SW applications. This bolt is compatible with the Law Tactical folding stock and the Echo trigger. CB45 Compensator Break. Manufactured to the highest quality standards right here in the U.S.A. Full auto tested to ensure that the compensator ports keep muzzle rise to a minimum. The twin chamber ports guarantee that every last bit of usable gas is utilized to kill recoil. Machined from US Mil-spec AISI 4140 steel and black nitride coated to provide a lifetime of abuse. Specifications for Stern Defense SD 16.1in MOD4 MLOK .40SW Upper Receiver Assembly: Manufacturer: Stern Defense Caliber: .40 S&W Barrel Length: 16.1 in Barrel Profile: Light Weight Barrel Twist Rate: 1-16 Firearms Threads Per Inch: .578x28 Muzzle Device: Comp Brake Color: Black Fabric/Material: 6061 Aircraft Grade Aluminum Handguard Length: 15 in Gun Rail: M-LOK Gun Make: AR Platform Gun Model: AR-15 Weight: 15.5 oz Bolt Carrier Group Included: MIL-SPEC Magazine Included: No Mount Type: M-LOK Package Contents: Stern Defense SD 16.1in MOD4 MLOK .40SW Upper Receiver Assembly Stern Defense 15 inch M-LOK rail(Barrel nut bolts etc.) Stern Defense 16.1 inch 40SW barrel. SD CB45 COMPENSATOR BREAK Stern Defense assembled upper receiver with dust cover and forward assist. Stern Defense SD BU40 Glock cut bolt. SD CH1 enhanced charging handle. What firearm models does the manufacturer say Stern Defense SD 16.1in MOD4 MLOK .40SW Upper Receiver Assembly is compatible with? The manufacturer says that Stern Defense SD 16.1in MOD4 MLOK .40SW Upper Receiver Assembly is compatible with AR-15Stern Defense 015SD15INMD4ML16.1INBR40SWKK: SD 16.1in MOD4 MLOK .40SW Upper Receiver Assembly 15in M-LOK Handguard .578-28 TPI 1-16 Twist Rate Black

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$600.00 at OpticsPlanet
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