
Availability: In Stock
The Leapers Inc. UTG Pro AR15 S4 Mil-Spec Stock Kit gives you a complete drop-in stock solution built tough for real-world use. If you're running an AR-15 and need a compact, adjustable stock that won't quit—whether you're training hard, running plates in a tactical setup, or just want a rock-solid upgrade from milspec basics—this kit handles it. You get everything in the box: the stock itself, extension tube, buffer, buffer spring, receiver end plate, and castle nut. Bolt it together and get to work.
The S4 design runs 4.28" with four adjustment positions, so you can dial in length of pull that works whether you're in a shirt, chest rig, plate carrier, or heavy load-out. The matte black impact-resistant polymer is made to take abuse without breaking, and Leapers builds these with tight tolerances—no wobble, no rattle, solid lockup every time. This is mil-spec geometry, meaning it'll integrate cleanly with standard AR-15 receiver extensions and components.
Whether you're upgrading from a bare-bones mil-spec stock or building a new rifle, this kit eliminates the parts-hunting phase. Everything you need to complete your receiver tube is included and ready to install.
| Brand | Leapers, Inc. (UTG Pro) |
| Product Type | AR-15 Mil-Spec Stock Kit |
| Model | S4 |
| Material | Impact-resistant polymer |
| Finish | Matte black |
| Length | 4.28" |
| Adjustment Positions | 4 |
| Included Components | Stock, extension tube, buffer, buffer spring, receiver end plate, castle nut |
| Compatibility | AR-15 mil-spec receivers |
Yes, this is a mil-spec stock kit designed for any AR-15 with a standard mil-spec receiver extension tube. The kit includes all components needed for installation.
The complete kit contains the S4 stock, extension tube, buffer, buffer spring, receiver end plate, and castle nut. You have everything needed to assemble a functional stock assembly.
The stock features four distinct adjustment positions with a 4.28" overall length. This allows you to customize length of pull for different use cases, including shooting in body armor or load-carrying gear.
Yes. The compact 4.28" length and four-position adjustability are specifically designed to work comfortably when wearing load-bearing vests and plate carrier systems, making it a solid choice for tactical or duty setups.



SKU: 115682698 • Width: 5.25in • Height: 2.12in • Depth: 9in • Weight: 1.31oz





Availability: In Stock
The Leapers Inc. UTG Pro AR15 S4 Mil-Spec Stock Kit gives you a complete drop-in stock solution built tough for real-world use. If you're running an AR-15 and need a compact, adjustable stock that won't quit—whether you're training hard, running plates in a tactical setup, or just want a rock-solid upgrade from milspec basics—this kit handles it. You get everything in the box: the stock itself, extension tube, buffer, buffer spring, receiver end plate, and castle nut. Bolt it together and get to work.
The S4 design runs 4.28" with four adjustment positions, so you can dial in length of pull that works whether you're in a shirt, chest rig, plate carrier, or heavy load-out. The matte black impact-resistant polymer is made to take abuse without breaking, and Leapers builds these with tight tolerances—no wobble, no rattle, solid lockup every time. This is mil-spec geometry, meaning it'll integrate cleanly with standard AR-15 receiver extensions and components.
Whether you're upgrading from a bare-bones mil-spec stock or building a new rifle, this kit eliminates the parts-hunting phase. Everything you need to complete your receiver tube is included and ready to install.
| Brand | Leapers, Inc. (UTG Pro) |
| Product Type | AR-15 Mil-Spec Stock Kit |
| Model | S4 |
| Material | Impact-resistant polymer |
| Finish | Matte black |
| Length | 4.28" |
| Adjustment Positions | 4 |
| Included Components | Stock, extension tube, buffer, buffer spring, receiver end plate, castle nut |
| Compatibility | AR-15 mil-spec receivers |
Yes, this is a mil-spec stock kit designed for any AR-15 with a standard mil-spec receiver extension tube. The kit includes all components needed for installation.
The complete kit contains the S4 stock, extension tube, buffer, buffer spring, receiver end plate, and castle nut. You have everything needed to assemble a functional stock assembly.
The stock features four distinct adjustment positions with a 4.28" overall length. This allows you to customize length of pull for different use cases, including shooting in body armor or load-carrying gear.
Yes. The compact 4.28" length and four-position adjustability are specifically designed to work comfortably when wearing load-bearing vests and plate carrier systems, making it a solid choice for tactical or duty setups.
SKU: 115682698 • Width: 5.25in • Height: 2.12in • Depth: 9in • Weight: 1.31oz


