

Product Description
Mount a Shield RMSc or SMSc optic to your Glock 21 without milling the slide. This low-profile slide mount replaces the rear iron sight with a slide-in rear sight and mounting plate, sitting flush with RMSc and SMSc optics for a clean fit. It will also accept the standard RMS, SMS, SMS2, and JPoint sights with a slight width overhang. The RMSw can fit, but may not seal because the plate is narrower than the RMSw and its gasket.
Product Highlights
- Direct rear-sight replacement for Glock 21—no slide milling required
- Flush fit with Shield RMSc and SMSc micro red dot optics
- Also accommodates RMS, SMS, SMS2, and JPoint (with minor width overhang)
- Low-profile design for improved sight alignment and holster compatibility
- Black finish to match Glock OEM 21 slides
Specs
- Product Type: Low-Profile Slide Mount / Mounting Plate
- Fit/Compatibility: Glock OEM 21
- Optic Compatibility: RMSc, SMSc; also fits RMS, SMS, SMS2, JPoint (RMSw may not fully seal)
- Installation: Replaces rear sight with slide-in rear sight and mount plate
- Color: Black
- UPC: 754590543422
- Manufacturer Part Number: MNT-G21-POLY-SMS-RMS
- Brand: Shield Sights
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