The UTG PRO AR-15 Ops Ready S4 Mil-Spec Stock Kit (brand part no. RBUS4DM) brings the same complete stock assembly as UTG’s black S4 kit to a flat dark earth finish, molded from impact-resistant, high-strength polymer. The kit includes a mil-spec extension tube, buffer, buffer spring, receiver end plate, and castle nut, so a builder isn’t hunting down separate parts to finish the lower. Its 4.28-inch stock body with 4-position adjustability gives a comfortable length of pull and easier shouldering when wearing a load-bearing vest or plate carrier system, and UTG holds it to tight tolerances for a secure, heavy-duty fit.

Key Specifications

• Molded from impact-resistant, high-strength polymer.
• Includes a mil-spec extension tube, buffer, buffer spring, receiver end plate, and castle nut.
• Stock body measures 4.28 inches with 4-position adjustability.
• Finished in flat dark earth.
• Built for heavy-duty use with tight tolerance controls.

Frequently Asked Questions

What’s included in this kit? A mil-spec extension tube, buffer, buffer spring, receiver end plate, and castle nut, along with the stock itself.

What finish does it come in? Flat dark earth.

Buy the UTG PRO AR-15 Ops Ready S4 Stock Kit, FDE

Finish your earth-tone build’s stock assembly in one kit. Order the Leapers UTG stock kit from our rifle stocks selection at our Lubbock, Texas gun shop for fast, direct shipping.