All-steel back up Magpul MBUS Pro Backup Sights. Fantastic rock-solid sights, the best on the market. Detailed review will be tomorrow.

Magpul MBUS Pro Backup Sights

Magpul MBUS Pro Backup Sights

Magpul MBUS Pro Backup Sights

Magpul MBUS Pro Backup Sights

You can get them on Brownells.

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