Strike Industries Enhanced Castle Nut w/ QD, Fits AR-15, Black SI-AR-ECNEEP-BK ARECN&EEPBK

Strike Industries Enhanced Castle Nut w/ QD, Fits AR-15, Black – SI-AR-ECNEEP-BK / ARECN&EEPBK (UPC: 708747545548) GunMag Warehouse+1

Upgrade the rear end of your AR-15 with the Strike Industries Enhanced Castle Nut with QD End Plate in black. This premium combo replaces your basic mil-spec castle nut and end plate with a stronger, more functional, and much better-looking setup—complete with an integrated QD sling mount for fast, secure sling attachment. Strike Industries+1

Purpose-Built Upgrade for AR-15 Builders

Unlike generic parts kit hardware, the Strike Industries Enhanced ECN & EEP are engineered from the ground up for both performance and aesthetics. The steel castle nut is lengthened to match the extended end plate, supporting more of the receiver extension’s threaded area while creating a clean, streamlined profile at the back of your lower receiver. Strike Industries+1

This is not just another castle nut—it’s a functional enhancement for serious AR shooters and builders.

Integrated QD Sling Mount – Ready for Modern Sling Setups

The star of this combo is the extended QD end plate with a centrally placed Quick Detach (QD) sling swivel socket. This QD point is pushed slightly rearward, away from the webbing of your primary hand, giving you: Strike Industries+2IPSCStore+2

• Better comfort under sling tension

• Less chance of pinching your hand during manipulations

• Improved control when working in tight spaces (vehicles, CQB, barricades)

• True ambi sling use for right- or left-handed shooters

Attach your favorite QD sling swivel in seconds and enjoy a solid, repeatable mounting point right where you want it.

Enhanced Castle Nut – Stronger Support & Clean Look

The enhanced castle nut is lengthened compared to a standard nut, which means it: MidwayUSA+2Palmetto State Armory+2

• Engages more of the buffer tube’s threaded area, improving support

• Helps resist loosening under recoil and heavy use

• Smoothly matches the profile of the extended end plate for a refined custom-build look

Constructed from durable steel with a black finish, it’s built to handle hard use while complementing most AR-15 color schemes. GrabAGun+1

Smart Features: QD Placement & Takedown Pin Convenience

Strike Industries didn’t stop at looks. The Enhanced Castle Nut w/ QD End Plate includes several smart, user-focused design touches: OpticsPlanet+2IPSCStore+2

• Centrally placed QD socket for ambidextrous sling setup

• QD location pushed back from the receiver to avoid pinching and improve ergonomics

• Set-screw–friendly design that simplifies the installation of the rear takedown pin and detent (no tiny spring launching across the room)

Compared to a standard end plate, this combo also slightly changes stock behavior: with most collapsible stocks, the fully collapsed position is eliminated to create the necessary clearance for the QD socket. This trade-off yields a safer, more usable QD mount without compromising most length-of-pull options. Strike Industries+2IPSCStore+2

Drop-In Installation for AR-15 Platforms

The Strike Industries Enhanced Castle Nut w/ QD, Fits AR-15 is designed as an easy drop-in upgrade for mil-spec AR-15 lower receivers: OpticsPlanet+1

1. Ensure your rifle is unloaded and safe.

2. Remove your existing castle nut and end plate.

3. Install or re-install your receiver extension (buffer tube).

4. Install the Strike Enhanced End Plate in place of your old plate.

5. Thread on the Enhanced Castle Nut, align and torque (do not exceed manufacturer’s torque recommendations).

6. Stake or secure per your preferred build practice and perform a full function check.

No permanent modifications are required, making this a perfect upgrade for new builds or existing rifles.

Ideal For: Builders, Upgraders & Sling Users

This Strike Industries castle nut and QD end plate combo is an excellent choice if you:

• Are building a new AR-15 and want higher-end hardware at the rear of the receiver

• Rely on a QD sling and want a reliable, ergonomic attachment point

• Want to upgrade from a plain stamped end plate to something more functional and visually appealing

• Appreciate parts that improve manipulation in tight spaces and under stress, not just on the bench Mounts Plus+2Palmetto State Armory+2

From defensive carbines and duty rifles to competition setups and premium custom builds, this combo brings real-world utility to the table.

Key Specifications – Strike Industries Enhanced Castle Nut w/ QD

• Brand: Strike Industries Gritr Sports+1

• Model Name: Enhanced Castle Nut w/ QD / Enhanced ECN & EEP Combo Strike Industries+1

• Part Number: SI-AR-ECNEEP-BK (also referenced as ARECN&EEPBK by some retailers) GunMag Warehouse+1

• UPC: 708747545548 OpticsPlanet+2GunMag Warehouse+2

• Platform Fit: AR-15 (long gun parts – castle nut & end plate) Gritr Sports+1

• Material: Steel castle nut and end plate

• Finish / Color: Black

• Features:

  • Extended castle nut supports more receiver extension threads

  • Extended QD end plate with centrally placed sling swivel mount

  • Ambidextrous sling use, QD pushed back for comfort and clearance

  • Easy drop-in installation, with features that simplify takedown pin and detent installation Strike Industries+2OpticsPlanet+2

Why Choose Strike Industries for Your AR-15 Rear-End Hardware?

Strike Industries has built a reputation for innovative, shooter-focused upgrades that blend form and function. The Enhanced Castle Nut w/ QD, Fits AR-15, Black SI-AR-ECNEEP-BK is a perfect example: it strengthens the buffer tube interface, cleans up the look of the rear receiver area, and gives you a professional-grade QD sling mount—all in one package. Strike Industries+2Palmetto State Armory+2

If you’re serious about your AR-15’s reliability, ergonomics, and appearance, this is a small part with a big impact.

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