Atrius Development 3 Position SIG MCX/MPX X-Series Super Selector Safety - ADG-FRS-AMBI-X

Atrius Development 3 Position SIG MCX/MPX X-Series Super Selector Safety

The Atrius Development Group FRS X-Series was designed to be compatible with a variety of Sig Sauer MCX®, MPX®, Rattler® platforms, and even Sig’s MCX-Spear LT Upper AR Conversion Kit.

Features

• Style: Atrius Ambi Selector Switch (original design)
• Configuration: Safe, Semi, Super-Semi
• Includes a new FRS lever with dimensions compatible with MCX/MPX product lines
• Universal design for Sig Sauer® gas piston platforms
• Installation: Drop-In Ready (No Modifications Necessary)
• Manufactured in the USA

Materials

• Corrosion-Resistant Black Nitride Finish
• Made of Heat-Treated 4140 Steel

Compatibility

• Platform Compatibility: MCX®, MCX-Spear LT®, MCX-Rattler LT®, MCX-Spear LT Upper AR Conversion Kit®, MPX PCC®, MPX-K®. Compatible with all generations (safety latch may need to be removed in early gens).
• Trigger Compatibility: Mil-Spec Triggers that come with MCX/MPX platforms.
Single-stage Mil-Spec triggers that do not have a U-notch or relief cut.

Not Compatible

• Some MPX’s come with drop-in cassette-style triggers that are not compatible with the FRS.
• Geissele triggers designed for the MCX/MPX and the Atrius G-LEVER are not compatible.
• MCX: The Two Stage Match Duo AR trigger from Sig is not compatible.
• MCX: Some MCXs come with a skeletonized AR trigger from the factory. This trigger is not compatible due to the U-notch/relief cut on the rear of its trigger bar.

Installation Steps for X-Series Ambidextrous Forced Reset Selector

1. Install X-Series FRS as you normally would any other safety selector.
2. Install your fire control group (trigger).
3. Insert the trip base on the left side of the receiver and marry it to the rear trigger pin.
4. Insert the trip clutch onto the track of the trip base and push all the way forward.
5. Press the trip base down so it’s under the rear takedown pin.
6. Ensure the entire trip hasn’t shifted during previous steps.
7. Install the upper receiver and perform a dry-fire check.