Fab Defense RBS/FBS Backup Sights

Fab Defense has just released a set of backup sights for rail mounting. These sights come in a set with a retail of $84.00. These are made from a proprietary polymer with a lot of strength. The sights will be available in a variety of colors.

The sights mount to the rail with a cross screw. The user just flips each one up and down. They don’t have a spring lever to deploy them but in this case it’s a plus. After they are flipped up they aren’t going to snag and break. They aren’t difficult to fold down but when raised they are rock solid with no movement. The plus I mentioned is related to striking them on a tree limb etc. They simply fold back without breaking a spring action.

Adjusting is very easy requiring no tools. As you can see in the photo a small wheel is just under the post and can be rotated to raise or lower the front sight. The rear sight has the usual side mounted adjustment.

What I like about these is the simple but sturdy construction as well as the ease of adjustment. Of course with that retail a street price will be closer to the upper $75.00–$80.00 range. They are less expensive and a good deal sturdier when compared to the Magpul sights.

Phil White

Retired police officer with 30 years of service. Firearms instructor and SRU team member. I still instruct with local agencies. My daily carry pistol is the tried and true 1911. I’m the Associate Editor and moderator at TFB. I really enjoy answering readers questions and comments. We can all learn from each other about our favorite hobby!


  • jtango44

    Terrible quality had a set on my hands and the quality is no good.

    • DiverEngrSL17K

      Where did you get your sights from? I’ve always had very good results with FAB Defense products, so it’s a bit surprising to hear this. Is it possible that you got a counterfeit item? I seem to recall a lot of people saying that certain Magpul products were sub-standard ( to put it politely ) until it was realized that they had bought counterfeits.

    • 7.62 Precision

      Where and when did you get them? I have been using several sets and there is no way they could be considered poor quality.

  • Clint Notestine

    my mako rear sight fell apart

    • DiverEngrSL17K

      Is it possible you got a sub-standard counterfeit product?

      • Entirely possible in fact likely. These are being brought in from our usual suspects and even branded as the real thing.

        • DiverEngrSL17K

          Hi, Phil :

          Thank you for your professional opinions confirming this. I had suspected as much ( as had 7.62 Precision and probably many others — it stands to reason, doesn’t it, based on old-fashioned common sense? ) simply because the sudden apparent deviation in quality and functionality based on negative reviews did not make sense at all.

          The same sort of progression in circumstances involving counterfeiting has impacted many other reputable manufacturers (such as Magpul ) in recent years, so it should come as no surprise to anyone.


      MAKO is just a distributor and they SUCK!

      • Mako

        When did you purchase the sight that broke? There are Chinese-made sights that are sold by a number of distributors as “Mako” sights. Prior to these FAB sights, which are new, we sold no backup sights. The FAB sights have a lifetime warranty.

        • Obviously anyone who post under an alias can’t be taken seriously.

          In fact the word best fitting these people I can’t say on the blog. Chances are they work for a company competing with FAB in the world of counterfeiting.

          They are not welcome and have been removed from posting.

  • JaxD

    That’s one cheap looking casting.

    • Just needs a bit of wet dry to get the small bits sanded off. It might take five minutes to get rid of those.
      You have to remember the very close up photo makes it look much more prominent than it really is.

      • DiverEngrSL17K

        I’ve had excellent results with the FAB Defense products I’ve used so far, and they have a close working relationship with the Israeli military ( like Meprolight ), which reinforces the argument for high quality Mil-Spec gear. I don’t see why a set of folding front and rear sights should be any different.

        For those readers and contributors who have had apparent quality issues with what are supposedly FAB-branded products, please be aware that there are many counterfeiters out there with sub-standard offerings ( just as in the case of Magpul products ).

        • Very true and as you said marked as the copied product.

          Something many of you may not know and that is those from counterfeiters from China are at SHOT and purchase products/photograph them then take them back and copy from the original.

      • JaxD

        I’ve been casting for 30+ years. No finished product has left my hands with flash like that.

        • 7.62 Precision

          It is a military product. It is manufactured to military standards. Aesthetics are secondary to function, reliability, and price. Users can clean military-type polymer products up if they like, or they can leave them as is, but government customers don’t like to pay for unnecessary hand-finishing.
          I am always amazed at the people who want military grade firearms and accessories to be finished like a fine Italian shotgun. The exterior finish should reflect the purpose.

          • DiverEngrSL17K

            I couldn’t have said it better myself. Excellent call, 7.62 Precision! People tend to forget that functionality is nearly always the first priority for military-grade weapons and accessories, and that a nice finish is simply a coincidental extra.

        • There’s not that much flash and it certainly won’t affect how they function.
          That and if it bothers anyone that can be removed in under 5 minutes with little effort.

  • gunslinger

    how tall are they compared to magpul, especially the rear sight?

    if it is the same or smaller, i’d love to have it under my scope. and at 1/2 the price of a rear magpul buis

  • Elliot

    These sights aren’t new and they aren’t $40. Phil, care to elaborate?

    • That price is direct from an executive with the company. They also are saying it’s a new product. Outside of what I said above that’s about it.

    • They are sending me some to test and write up—

    • 7.62 Precision

      They should run about $84 on the street.

      • You know I’ll be the first to admit when I make a mistake and I certainly did make one. We were talking price and things were a bit confused or I was:-)
        Anyway the representative emailed and gave me the correct price which is indeed in the $84 range depending on where you get them.
        I’ve changed the post to reflect the correct price and my error.

    • I posted the error below

  • Lance

    Hope they come in black or OD white and tan don’t look well on a AR.

  • Phil Hsueh

    You sure you have your info right because I’m not seeing them being sold as a set anywhere, even the Fab Defense website shows them being sold individually and they’re going for $45 for the rear and $30 for the front on Amazon and the listing says that there’s a spring locking mechanism on the rear. I hope that this a brand new set that they’re showing at SHOT because I’d love to get a decent set of b/u sights for $40 for the set.

    • All I can say is what I was told. I’m not saying they can’t be wrong but $42 was the quoted price.

      • Phil Hsueh

        Well, I hope that you’re right and that the rep didn’t misspeak and they really are $42/set because that would be awesome. Be sure to post any updates on these as you find out more, esp. when they’ll be available.

    • I posted about my error above—

  • FABFan!