The GrovTec US Inc 3.8 Inch 9 Slot Stock AR Black Anodized Picatinny Rail (GTSW190, UPC 811071011907) is a compact aluminum rail section designed to add a MIL-STD-1913 Picatinny interface to AR-style rifle stocks. This 3.8" rail provides nine usable slots, creating a standardized mounting surface for a wide range of compatible accessories on AR platform stocks.GrovTec+2Sportsman's Outdoor Superstore+2
Model Identification and Part Numbers
This rail section is identified by several common catalog and tracking references:
Manufacturer: GrovTec US Inc
Model / Description: 3.8 Inch 9 Slot Stock AR Picatinny Rail
Manufacturer Part Number (MPN): GTSW190
UPC: 811071011907Chadwick Armory+2Winchester Arms+2
These identifiers allow straightforward cross-referencing with distributor, retailer, or inventory systems for buyers and armorers who need precise part matching.
Design, Construction, and Finish
The GrovTec GTSW190 rail is precision CNC machined from lightweight, solid aluminum stock. The machining process is intended to provide consistent dimensions and a clean rail profile with properly formed Picatinny slots for reliable accessory interface.GrovTec+2AR15Discounts+2
Key construction details:
The Type III hard anodized surface is designed to increase wear resistance and corrosion resistance under normal use, while the black finish provides a low-reflective appearance compatible with most AR stocks and furniture.
Picatinny Interface and Compatibility
The GTSW190 uses a MIL-STD-1913 Picatinny rail pattern, which is a widely adopted standard for firearm accessory attachment. This pattern allows mounting of compatible devices such as optics risers, laser modules, compact scopes, offset sights, sling interfaces, or other rail-mounted components, as long as they are designed for Picatinny sections of similar length.GrovTec+2AR15Discounts+2
The rail is specifically described as a Stock AR rail section, intended for installation on AR platform stocks or similar surfaces where a small rail segment is required rather than a full-length handguard rail. Retailer listings frequently categorize it as an AR-15 accessory, further indicating its intended use with AR-style rifles.Chadwick Armory+2Abide Armory+2
Mounting Hardware and Hole Spacing
GrovTec includes mounting hardware with the GTSW190 to support typical stock or buttstock installations:
Included hardware: 2 hex-head screws (10-32, approx. 0.375" length), 2 washers, and 2 threaded flat steel backplates, plus an Allen key for installation.GrovTec+1
Mounting method: “Sandwich style” installation, where the rail sits on the exterior of the stock and the backplates sit inside, clamping the stock material between them when the screws are tightened.GrovTec
For the GTSW190 specifically, GrovTec publishes the following hole spacing range:
This range gives installers a reference for drilling or aligning existing holes in synthetic or wood stocks to ensure a secure fit.
Dimensions and Weight
While the rail itself measures about 3.80 inches in length with nine Picatinny slots, overall package dimensions (including packaging) listed by some retailers are approximately 5.10" × 2.80" × 1.00".Winchester Arms+1
Additional technical data:
Size / length: 3.8" rail section
Slot count: 9 slots
Material: Aluminum
Approximate listed weight: Around 0.15 lb (total product weight, including packaging, varies slightly by vendor).Chadwick Armory+1
These dimensions place the GTSW190 in the compact rail category, suitable for adding just enough rail space for a single device or small cluster of accessories without significantly altering the overall profile of the rifle.
Typical Applications
Because it is a short Picatinny stock rail section, the GrovTec GTSW190 is often used in configurations where a user needs a small standardized mounting surface on the buttstock or rear portion of an AR platform rifle. Typical accessory types that may be attached include:
Rail-mounted sling adapters or QD sling bases
Small optics or sighting aids designed for rear mounting
Compact lights, lasers, or ancillary devices that use MIL-STD-1913 interfacesAR15Discounts+2Georgia Gun Store+2
Actual usage should remain within the accessory manufacturer’s recommendations, particularly regarding weight, recoil forces, and mounting surfaces.
Installation Considerations
The included hardware and Allen key are intended to make installation straightforward for users comfortable with basic gunsmithing tasks:
Positioning: The rail is aligned on the chosen location of the AR stock, ensuring clearance for the full range of adjustment of the accessory that will be mounted.
Hole layout: Holes are marked to match the supported center-to-center spacing range.
Drilling / fitment: Properly sized holes are drilled through the stock material according to the hardware specifications.
Sandwich mounting: The threaded backplates are placed internally, the screws and washers are installed from the rail side, and the assembly is tightened securely using the provided Allen key.GrovTec+1
Users should follow all manufacturer instructions and any applicable gunsmithing best practices to avoid damage to the stock or hardware.
Technical Specifications (Summary)
GrovTec US Inc 3.8 Inch 9 Slot Stock AR Picatinny Rail – GTSW190
Brand: GrovTec US Inc
Model: 3.8 Inch 9 Slot Stock AR
Part Number: GTSW190
UPC: 811071011907Chadwick Armory+2Winchester Arms+2
Type: Stock-mounted Picatinny rail section
Interface standard: MIL-STD-1913 Picatinny
Length: 3.8" (approx. 3.80")
Slot count: 9 slots
Material: Aluminum
Finish: Type III black hardcoat anodized
Category: AR / AR-15 platform accessory
Mounting hardware: Hex-head screws, washers, threaded backplates, and Allen key included
Hole spacing (GTSW190): Min ≈ 1.53", Max ≈ 2.40" center-to-centerWinchester Arms+3GrovTec+3Sportsman's Outdoor Superstore+3
The GrovTec US Inc GTSW190 3.8 Inch 9 Slot Stock AR Black Anodized Picatinny Rail is a compact, aluminum rail section with a hard anodized finish, designed to give AR platform stocks a standardized MIL-STD-1913 attachment surface. With its 3.8" length, nine slots, included mounting hardware, and published hole spacing range, it provides a defined technical solution for adding accessory compatibility to AR-style rifle stocks in a controlled and repeatable way.
The End
