In stock
FAB Defense RBS AR-15 Iron Sight Rear Flip Up - FX-RBS
In stock

FAB Defense RBS AR-15 Iron Sight Rear Flip Up - FX-RBS

SKU 165451214
Model Number FX-RBS
Brand FAB Defense
UPC 7290105941992
This product is fulfilled by a PSA Partner and shipping times may vary.
Customers must read Compliance Information before purchasing.

Product Details


Attachment: Picatinny Rail

Material: Polymer

Finish: Matte Black

Height: 0.55"

Deployed Height: 1.65"

Length: 2.04"


The Fab Defense RBS is an advanced, dual aperture, durable and low-profile rear backup sight. It can be used with any front sight and was designed for more accurate aiming and faster target acquisition. Windage is easily and quickly adjusted without tools. The RBS is readily mounted on any 1913 Picatinny rail, making it ideal for use on AR-15 platforms and on the FAB Defense KPOS. An ergonomic angel-wing shaped shroud helps center the image with any front sight, and when used with a matching FAB Defense FBS front backup sight, it creates a precise optical tunnel that ensures more accurate aiming and faster target acquisition.


  • 3mm and 1.5mm aperture for different light levels
  • Instant spring locked deployment mechanism
  • No tools needed for adjustment
  • Low profile when folded, will not catch on gear or webbing


Q & A


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All NFA Rules Apply

These items are controlled by the U.S. Government and authorized for export only to the country of ultimate destination for use by the ultimate consignee or end-user(s) herein identified. They may not be resold, transferred, or otherwise disposed of, to any other country or to any person other than the authorized ultimate consignee or end-user(s), either in their original form or after being incorporated into other items, without first obtaining approval from the U.S. government or as otherwise authorized by U.S. law and regulations.