Truglo M&P TFO TG131MP has better fit with S&W Shield  
By James Nicholas

 Truglo only has one version of Tritium Fiber Optic TFO sights sights for the Smith & Wesson series pistols. Since the TFO's were released for the M&P series several years ago and the Shield has only been released to the public less that two years. The M&P TFO was never designed with the Shield in mind. The Shield shares the same sights height and dovetail dimensions as the larger M&P pistols in every way except for the width of the dovetail. What this meant was that the older M&P TFO was able to be used with the newer pistol with no real functionality issues. For the last two years the older TM&P TFO sights have done fine and got the job done. 

For looks: On the internet you will hear that the older M&P TFO's did not fit and would hang off the slide. The fit was SO BAD that the sight would catch on everything and slow you down drawing your pistol enough that they were unusable.  Well I am here to tell you that was not the case, and it was refreshing for S&W to have the forethought to use the same dovetail. What this meant was that instantly a brand new pistol already had aftermarket sights available for use. I was one of the first ones in the country to get a released Shield and within an hour of picking it up, I was already customizing it to fit me. A couple of weeks later I posted on XDTALK about the adventure of refinishing the pistol, adding sights and Apex Trigger components. I have to do this, I believe it is my duty to experiment on my own firearms before I ever touch a customers firearm. So if you were to call me since then and ask about the fit of the Older M&P TFO's on the Shield I would have told you they are good to go. You would not have any issues and the sights are so great they far out weigh the slight overhang. From a couple feet away you would never even notice that there was any. The rear sight only hangs over the dove tail less than 1mm on each side. Unless you really look for it you cant see it. It will not catch on anything including the tightest of leather holsters. The back over hang is so slight that it would not interfere with anything and the angle of the back of the sight actually matches the angle of the back of the slide. 

In talking with Truglo the solution is not as easy as you would think. If you make the width of the TFO small enough to perfectly fit the Shield and its slide radius. The resulting TFO would not look good on the larger M&P's since the drop safety would start to be exposed as illustrated to the left red arrow. If the hole in the dovetail for drop safety were exposed all kinds of debris could gum up the safety potentially disabling the whole pistol. Not to mention the safety concern or the effect on the trigger pull. Not taking this lightly Truglo had to find a sight shape and width that would fit equally well with both the larger M&P's as well as Shield's. Truglo wants to avoid having multiple versions of M&P TFO sights other than color options. This is great for dealers since it cuts down on having to stock multiple SKU's. For customers this cuts down on confusion on what sight to buy, there is only one size and it comes in with a Green Front / Green Rear or Green Front / Yellow Rear.  What Truglo settled on was to shave off 0.040" or 1/25th" off the sides effectively shorting the width and flattening the dovetail extension sides.  On the larger M&P's the new modified M&P TFO is still wide enough that it will center in the dovetail, fully cover and protect the drop safety. But the sight is smaller in width enough that it will not stick out beyond that flats of the slide's side, it don't overhang any more. 

The M&P TFO has not changed in it's outward appearance. The rear sight is still the same length and did not change from the older version. The width has been reduced 1/25th of an inch to better bridge the differences in M&P slides. We used two different colored rears in this article to represent the different generations. The green sight in the article will always be the older wider M&P sight. The yellow will be the newer generation two S&W TFO.  

Both generations of the TFO rears next to each other to show the difference in width. Now the yellow TFO ends seem flatter on the ends than the previous generation.

Take note of how the dovetail extensions stick out from the Shield slide. The green arrows point out the older generation TFO, the yellow show the new TFO.  As I said earlier in the article the older version was not as bad as people described and most people would never have noticed unless you pointed it out to them. Then never hung off enough to ever interfere with the function or use of the pistol. 

The slide above and to the right shows that when the newer TFO's are properly centered in the Shield you can just barely see a sliver of the dovetail on each side of the dovetail extension. 

A different angle to show the fit of both generations of TFO in the slide. 

A top view of both generations of TFO rear sights. The yellow newer version is just a little bit more tucked up in the dovetail.  

A side view of the TFO rear on a Shield Slide.

The only way to tell if you have an updated version of the S&W TFO other than measuring is to check the back of the package. Just above the UPC code you can find the date code. The first number is the year and the second number is the month. So the older versions green arrow was made in the year 2013 month of February. The newer updated version started to be manufactured in 2013 in the month June. Even with this update there is only one model number for all M&P pistols that is TG131MPT. Again TG131MPT fits all M&P pistols including the shield. The only option comes with the yellow rear version thats add a "Y" on the end of the model number TG131MPTY. 

UPDATE from Truglo 

Helpful article.
The actual reduction was .034" (.017") from each side. (The article rounded those numbers) This was done on all M&P series sights from TRUGLO, with the intent (as stated in the article) to make one size that properly fits all M&P series pistols with the same dovetail. (This excludes the C.O.R.E. model and .22 Compact) The newer TFX™ and TFX™ PRO sights use the smaller width as well. As mentioned in the article, the date is a good way to determine which version who have. Additionally, newer TRUGLO handgun sights use a different package design. 

Package Image here:

Checking the date may be helpful on older packaging, but all M&P sights in the newer packaging fit the shield without overhang. The date / fitment issue is only likely to occur in smaller resellers that have not restocked in a while. Distributors and volume dealers have been receiving the newer sight design for some time. 

Thank you,