Red dot mounts for Glock 21

Discover red dot mounting solutions designed for the Glock 21—ideal for upgrading your pistol with a modern optic. These mounts fit into the rear sight dovetail, allowing you to install a red dot without altering your slide permanently.

Using a Glock MOS model? The mounts on this page are intended for standard Glock 21 slides. If you own a MOS version, visit our dedicated section for optics-ready plates: optics ready plates for Glock MOS.

Red dot mounting options for Glock 21

Whether you’re fine-tuning your setup for duty, defense, or competition, these mounts offer a rock-solid fit—no slide milling, no gunsmithing. They’re built for the standard Glock 21 dovetail cut, making optics installation straightforward and reversible.

Compatible with major red dot sights

Our current selection for the Glock 21 covers:

• Shield RMSc

Why mount a red dot on your Glock 21?

Adding a red dot to your Glock 21 boosts both speed and precision. Our mounts provide:

• Faster target acquisition and improved transitions
• Increased accuracy under pressure
• No slide cuts—fully reversible installation
• A stable platform for red dots on the Shield RMSc footprint

Upgrade your Glock 21 into a red dot–ready platform with minimal effort—no permanent changes required.

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accessories that are compatible with GLOCK pistols. For genuine
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