Armaspec
Captured multi-stage recoil spring that replaces the buffer and spring in a carbine tube, available in C, H, H2, and H3 equivalent weights.
The Armaspec Stealth Recoil Spring is a captured, drop-in replacement for the standard buffer and spring in a carbine buffer tube. Instead of a separate buffer and coil spring, the SRS combines the spring and weight into one self-contained, multi-stage unit that keeps the spring from rubbing against the buffer tube wall. That contact is the source of the gritty feel and the spring twang in a stock setup, so the SRS delivers smoother, quieter cycling the moment it goes in.
This Gen 4 version is offered in four weights so you can match it to your gas system: C at 3.3 ounces, H at 3.8 ounces, H2 at 4.7 ounces, and H3 at 5.6 ounces. The H2 is the most common pick for suppressed carbines and overgassed mid-length builds, mirroring the role of a standard H2 buffer but with the captured spring quieting and a multi-stage impulse that takes a little edge off felt recoil. Construction is stainless steel, and the Gen 4 redesign replaced the earlier weight o-ring with a roll-pin fastening for durability.
The SRS sits between a simple spring upgrade and a full premium captured system like the JP SCS. It costs more than a Sprinco spring but less than the JP, and it is fixed-weight per unit rather than adjustable. Treat the weight choice as a starting point matched to your barrel and gas length, and verify reliable lock-back and ejection after install rather than assuming any single weight is universally correct.
Add the Armaspec Stealth Recoil Spring SRS Gen 4 (H2) to your build and see how it enhances your platform.