Atrius Development Forced Reset Selector (Mil-Spec Profile)
Single-side FRS with traditional mil-spec selector lever for retro and clone builds
- Price
- $199
- Weight
- 0.4 oz
- Brand
- Atrius
- Category
- Controls
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Features
- •90-degree throw
- •Mil-spec selector profile
- •Right-hand only
- •Heat-treated 4140 steel
- •Three firing modes
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Atrius Development Forced Reset Selector, Black, ADG-FRS-S-MS
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Overview
The Mil-Spec Atrius FRS is a single-side forced reset selector built for retro builders, M16A4 clones, and Colt-pattern rifles where the standard Atrius lever looks out of place. Mechanically it is identical to the original Atrius FRS: same heat-treated 4140 steel, same 90-degree throw, same three firing modes (Safe, Semi, Full-Semi). The only difference is the selector lever itself, which uses the traditional mil-spec profile with classic ridges and a pointer instead of the aggressive textured Atrius lever.
The lever shape matters more than it sounds. A retro A1, A2, or M16A4 clone with a tan furniture loadout looks wrong with the modern Atrius lever sticking out of the receiver. The mil-spec variant fixes that by mimicking the geometry of a standard AR-15 safety selector while delivering the same forced reset functionality underneath. It also gives clone builders running faux full-auto markings a period-correct lever to match the rest of the build.
Drop-in installation with mil-spec fire control groups (some minor fitment may be required), MPN ADG-FRS-S-MS, made in the USA. Atrius ships this in the same black bag as the standard single-side FRS, watch for counterfeit listings on third-party marketplaces. At $199 it matches the standard single-side on price and sits $50 below the ambidextrous version.
Key Features
- Mil-spec selector lever profile with traditional ridges and pointer
- Three firing modes: Safety, Semi, and Full-Semi with instant trigger reset
- Drop-in installation with mil-spec fire control groups
- Heat-treated 4140 steel with corrosion-resistant finish
- Mechanically leveraged design reduces rifle wear vs FRT triggers
- Crisp 90-degree throw with positive detent engagement
- Designed for retro builds, M16A4 clones, and Colt-pattern rifles
Pros
- +Period-correct lever shape for retro and clone builds
- +Cheapest variant in the Atrius FRS lineup at $199
- +Same internals and forced reset performance as the standard single-side
- +Drop-in with mil-spec FCGs that have no relief cut
- +Heat-treated 4140 steel construction, made in USA
Cons
- −Right-hand only, no ambidextrous selector
- −Lever profile is the only difference from the standard $199 single-side
- −May require minor fitment during installation
- −Legal status varies by state, verify local regulations before purchase
- −Limited trigger compatibility (mil-spec FCG without a relief cut; stock Geissele triggers need the G-Lever variant)
Detailed Specifications
- Material
- Heat-treated 4140 steel
- Finish
- Corrosion-resistant coating
- throw
- 90-degree
- positions
- 3-position (Safe/Semi/Full-Semi)
- hand
- Right-hand only
- leverProfile
- Mil-spec (traditional ridges and pointer)
- compatibility
- Mil-Spec AR-15 (.223/5.56/.300 BLK)
- fireControlGroup
- Mil-spec FCG without a relief cut (stock Geissele pairings need the G-Lever variant)
- triggerModification
- None for a mil-spec trigger without a relief cut; a super safety cut trigger has to be filed to fit
- installation
- Drop-in (minor fitment may be required)
- mpn
- ADG-FRS-S-MS
- upc
- 850079014084
- madeIn
- USA
- colors
- Black
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