Chamber Flag

MT Chamber Flags

MT Chamber Flags

Gun safety is the most important foundation to our hobby. Sometimes a product comes along that is so simple and easy to use, it makes using firearms safely almost idiotproof. I say almost, because anything can happen. However when handling a firearm, at least a semi-automatic handgun or rifle where accidents and negligence are more prone, and chamber flag can guarantee that a firearm has been inspected, is cleared, and is safe to handle.

MT Chamber Flags

Chamber flags aren't a new invention, they've been around what seems like forever. Often they will come packaged with a firearm from the factory, and many gun owners either leave them in the box, or cast them aside like the safety locks they probably have dozens of. Even though many gun owners don't use chamber flags, many shooting ranges require flags to be used so that Range Officers or other shooters can all verify firearms on the bench are clear, empty, and inert before proceeding downrange to check targets, with the peace of mind there aren't any accidentally loaded firearms pointing at their backs.
I believe the generic chamber flags are inherently too small, serving more as a chamber block than an actual flag to visibly signal the firearm's status around the vicinity. Fortunately there is a better designed alternative chamber flag that does a much better job.

MT Chamber Flags

M-T Chamber has created a chamber flag that is highly visible because of it's length, and integral pull handle that increases the visible surface area from 360 degrees around the firearm. MT Chamber flags also come in two caliber ranges, fitting either 380-40 caliber chambers with the SBT 380/40, or 45 auto and .223 (AR15) chambers with the SBT 45/AR15. This gives the user the ability to toss either or both chamber flags in their bag and utilize for nearly any semi-auto firearm while at the range.

MT Chamber Flags

Chamber flags aren't just useful at the range. FFL's and gun shops often use a chamber block or similar device to keep guns in the glass counter clear and safe, and easily inspectable at a glance. Also law enforcement need ways to keep found or seized guns cleared or identified as inspected and cleared in a fast efficient manner so they can do the task at hand. The MT Chamber Flag accomplishes all of the above much better than other flags on the market today.



MT Chamber Flags


I tried the MT Chamber flags in just about every semiauto firearm I own, and while the pros are very apparent (high visible, multi caliber compatibility) there are a few cons that keep my review from glowing as brightly as the flags themselves. The plastic construction is very flexible and somewhat soft. In fact, if you let the slide / bolt close with the full force of the spring, there will start to be chew marks into the back of the flag. While some normal wear and tear won't effect the performance of the flag, I would recommend assisting the bolt or slide close more softly to get the most longevity for your dollar. My only other gripe is that the flags don't have any indication as to their caliber range incorporated into the mold. Instead of having the logo and website on both sides, it would have been nice to have the model number or at least calibers on the flags themselves. Other than that, the MT Chamber flags are a decent evolution of the safety device that many of us overlook.

Firearms Insider Reviews – 8 Key Points

Claim to Fame:  The M-T Chamber is the only product currently on the market that is visible from 360 degrees, and guarantees a firearm has been inspected, unloaded, and is safe when properly installed into the chamber.

Target Market:  Police departments, shooting ranges, CPL instructors, and homeowners.

FNBs (Features & Benefits of this product):

  • Will work in most semi-auto handguns and rifles given the correct chamber diameter.
  • The STB-380/40 fits handgun .380 caliber or larger.
  • The STB-AR15/45 will work in any AR-15 style weapon and also in .45 caliber or larger semi-automatic handgun.
  • Protrudes more than other standard chamber flags for better visibility

What other aesthetic options or finishes are available?: Available in many different colors Safety orange is standard.

What others are saying?:

no reviews found

Price point:

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Our Rating:


  • High visibility when chambered in pistols and semi-auto rifles
  • Length of flag offers visibility in AK-47 chamber
  • Multi calber compatibility


  • Polymer is very flexible / can bend flag completely over
  • Polymer is soft and will easily deform/wear over time with rough use
  • No indication of caliber range/model molded into flag itself

Score: 7.0 Good



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