Holster Retention Deep Dive – How To Test Retention (and How NOT to)

15 Minute Read

Should a kydex holster click when the gun is inserted?

Short answer:  Sometimes.

Longer answer: The “click” feel and sound is a feature of certain holster designs.  On its own, it doesn’t tell you much about whether or not the holster is any good.  A click can happen for different reasons, not all of them positive. Here’s a quick primer on what the click really means, how it works, and how to test your holster’s retention. We’ll focus on inside the waistband holsters (IWB), since they are most often used for concealed carry.

What is “retention?”

The important thing to know is the foundation concept of holster “retention,” which is basically just making the gun stay inside the holster when you need it to stay, while still being accessible for a safe and unobstructed draw. The gun should stay securely in place on your body without falling out of the holster, even through extreme movements such as jumping, grappling, parkour, or break-dancing. When your holster has good retention, you can bust a move with confidence.

Why do kydex holsters click?

There are a few ways to get retention when you’re making a holster. For IWB holsters, the most common ones are friction and interference. 

Friction is, well, friction. Friction between the gun (or light) and the holster shell holds the gun in place. The kydex squeezes tight around certain features of the gun (or light), and the harder the squeeze, the tighter the retention.  Inserting a gun into a holster with friction retention feels gradual, and less like an abrupt click.

Interference is when the kydex is molded into a depression or void on the gun, most often the trigger guard. When the gun is inserted into the holster, the two halves of the kydex shell spread apart, and when they snap back together into the depression, you hear that distinctive “click” sound. The shape and depth of the indentation is a factor in how the retention feels and how “clicky” it is (though it’s not the only factor).

A holster can use a combination of both friction and interference fit – it doesn’t have to be purely one or the other.

Interference fit. When the gun is inserted, you can see the two sides of the holster spread apart, then snap back together. That’s what gives you the “click” feeling and sound. Watch how the small indentation in the trigger guard causes this effect.

Are holsters SUPPOSED to click?  Is it bad if they don’t click?

Holsters are supposed to securely retain the gun when it’s worn on the body. Period. Whether or not they click is window dressing – it’s the job that’s important. The holster should retain the gun on your body through a variety of everyday and extreme movements.

How should you test retention?

There are good and bad ways to test holster retention. We’ll start by talking about how NOT to test a holster, then we’ll briefly explore how IWB holsters are designed, why it matters, and the right way to test retention.

How NOT to test your holster

Contrary to popular belief, you shouldn’t test an IWB holster by shaking it upside down. The “shake test” is a popular internet sensation that you’ve probably seen before. To do the shake test, the user holds the holster upside down and vigorously shakes it. If the gun falls out, the holster “fails.”  It’s a popular test because it’s simple and easy.  As usual, though, the truth is a little more complicated and a lot less widely known. 

The shake test makes intuitive sense.  Of course you don’t want your gun falling out during vigorous movement, and shaking the gun seems like a good way to simulate vigorous activity.  However, the shake test actually has nothing to do with the real-world performance of the holster.  That’s because holster retention alone isn’t what keeps the gun on your body when you’re actually wearing it. Many poor quality holsters will “pass” the shake test, and many good quality holsters will “fail” it. You can also manipulate the results of the shake test, as we’ll demonstrate on video below

Like many internet fads, the shake test is based on a grain of truth. When you gently tip the gun upside down, it shouldn’t fall freely out of the holster. There should be at least some resistance, though how much can vary depending on the weight of the gun. Generally speaking, it’s reasonable to expect to handle the holster for routine activities (like donning and doffing, bathroom breaks, etc.) without your gun falling out, provided you use a reasonable amount of caution. However, there’s a world of difference between careful handling practices and shaking the gun upside down. 

Why isn’t the “shake test” accurate?

IWB holsters are designed to be worn between your belt (or Enigma) and your body. The pressure of your belt against the front of the holster provides inward force. Additionally, your body provides surface area, friction, and pressure on the other side of the gun, effectively sandwiching the gun in between two sources of pressure.  This belt/gun/body pressure sandwich adds a ton of extra retention.  It’s why you can do cartwheels, jump on a trampoline, or survive a car accident while wearing a well-designed holster – even though those things generate much more force than the shake test.

Rollover car accident while carrying.

PHLster Concealment Workshop member David Appleman survived this rollover while carrying a G43X in a PHLster Pro Holster, worn in the appendix position. Despite the severity of the accident, his gun stayed put and he did not sustain any major injuries. (Note that he was wearing his seatbelt correctly.)

Two things about that concept are important.  One, when you shake an IWB holster upside down, you’re missing the whole pressure part of the pressure sandwich. So your retention will feel much lighter than it would when wearing the holster.  Two, if you try to adjust your retention to make it feel right in your hand, it’s going to be a lot tighter than necessary to accomplish the job of retaining your gun on your body.

In the video below, note how simply changing where you hold the holster changes the retention. Holding the edges of the holster allows the gun to fall out easily because no pressure is applied to the face of the shell.  However, when you squeeze the shell where your belt would apply pressure, it makes the retention much tighter.

So how DO you test your holster’s retention?

Since body contact is a big part of holster retention, and since all bodies are different, the most accurate way to test your holster’s retention is to wear it. That means putting on your holster and belt or Enigma and unloaded gun (we recommend using a Barrel Blok for an added layer of safety). Get everything situated the way you plan to wear it in real life. Test retention by performing a range of activities, gradually ramping up the difficulty level as you are able. Jumping jacks, burpees, sprints, and hip bridging exercises are a great start. Make sure the gun stays in place through a wide range of extreme movements.

When testing your draw, make sure your draw stroke is quick and clean, and that the gun releases from the holster crisply when you need it to. Use quick, confident movements. A hesitant draw will often make your holster retention feel tighter than it really is. 

For a great video demonstration of how to test holster retention, check out the “retention” segment in this video from Armed and Styled.

So is the click necessary?  Does it mean the holster is well made, or safer?


Basically, take a click with a large grain of salt. A clean, precise click without slop CAN mean the holster is made well.  Sometimes.  Or not. It’s only one factor out of many factors that are important in a well made holster. 

Some holsters feel clicky because they are made poorly. For example, some holsters are molded with interference into the ejection port, which definitely makes a resounding CLICK, but also causes many other problems, such as excessive wear to the holster and to the finish of the gun.

Other holsters don’t feel clicky at all, but are well made and have excellent retention. The performance of the holster is what matters – not the click. 

When you test a large enough variety of good and bad holsters, you start to develop a sense for what good retention feels like. Whether or not the holster clicks, you want the retention to feel precise and intentional. It’s a feeling that’s hard to describe, but once you’ve handled some top tier holsters, you’ll know it when you feel it.

Do PHLster holsters click?

Some models do, and others don’t.

PHLster holsters are compression formed to tight tolerances, and every holster is test-fit before it leaves the shop. The decisive click you feel with our interference fit holsters (such as the Skeleton or PHLster Pro Holster) comes from precision along every contact point with the gun, not just the trigger guard. Our friction fit holsters (such as the Floodlight) are smooth, precise, and authoritative.  

What about guns with lights?

Most weapon-mounted lights are wider than the trigger guard of the gun, which means using interference fit around the trigger guard won’t work. If you tried, the light wouldn’t be able to pass through the gap.  In other words, the entire lower half of the holster needs to be wide enough for the light to fit, so molding around the skinny little trigger guard won’t cut it.

Instead of using the trigger guard for retention, many light bearing holsters use the light itself for retention. Again, two types of retention are possible – friction and interference. Friction fit is when the kydex is fitted tight to the light. The amount of pressure on the light determines how tight the retention is. Your belt and body still play a major role, so make sure to test retention as the holster is worn.

With lights, interference fit is sometimes possible, but not always. It depends on a) the shape of the light, and b) whether the holster is made for one specific gun, or if it’s made to fit the light and accommodates many guns. If the light has a shoulder or depression where you can mold in some interference, you can sometimes get a “clicky” effect when molding to the light. But that’s impossible with some lights, and they are friction fit only.


If you’ve made it this far, you now know more about retention than the VAST majority of gun owners. We hope you will use your knowledge to help others who are not as far along on the journey. Thank you for reading!

Do you need extra holster length?*

*If you’re carrying a longer-muzzled gun or a revolver, adding extra holster length may not be necessary for you, but for short semiautomatic guns, it’s often helpful.

Guns with short muzzles can be top-heavy and difficult to conceal comfortably. To solve this, some holsters have extra length added to the muzzle end. Like the keel on a boat, the extra muzzle length helps balance the holster, making it more comfortable and easier to conceal. This is especially true if you have a bit of a belly, which tends to push the grip out more and make the muzzle dig in.

Note that while extra muzzle length reduces grip printing, it can increase muzzle printing, which can be a concern with lower carry positions and tight fitting pants such as leggings or yoga pants. 

Learn more about the Keel Principle here.