Mack Weldon Silver XT2 Review

7 min readAug 5, 2017

Can silver in your underwear really make a difference? This is what I attempt to figure out.

Underwear Specifications:

  • Model: XT2 Silver
  • Brand: Mack Weldon
  • Material(s): 84% Pima Cotton / 10% XT2 Silver / 6% Lycra
  • Style: Standard Boxer Brief
  • Price: High $34 USD
  • Approximate Steps To Chafe: ASTC 18000+

Initial Impressions

I saw these, and when I saw “silver” they caught my eye. Being a giant nerd when you tell me that you engineer something with advanced fabrics I start to drool a little. The nerd-boner pops up in my mind, and I start getting wild ideas in my head, especially when it comes to underwear. Every new pair of “advanced” underwear I see makes me think that these might be the pair that solves all my problems.

I downloaded the XT2 white paper to find out what it was about. To answer your burning questions. Yes, there is a whitepaper on a fabric in underwear. Yes, I did indeed read said whitepaper. Finally, yes, I would, and will read any more whitepapers if other brands provide them.

The XT2 fabric is supposed to stop the odor, and be antimicrobial. Mack Weldon says it’s also supposed to keep you cool as well. The pima cotton is used for absorbing moisture. While the Lycra is essentially the spandex that lets the fabric stretch. All of these magical fibers combine to make “Super Underwear!”

After getting past the initial sticker shock I ordered my pair to being my super serial testing.

Build and Quality

Mack Weldon has excellent build quality. As you can see from the pictures below. A ton of care is taken to provide a waistband that is multiple layers. Legs bands that hold the underwear in place. They also provide a completely different piece of mesh fabric to allow easier drying around the top back of the underwear. The sweat rolls down your back, then it hits, and collects in the the mesh. As opposed to just passing down to the bottom of your underwear. Another attention to detail for real world usage is there isn’t a single inseam at the middle underside of the underwear. There are two inseams that are offset. This cuts down on rubbing away at your inseam. Really good foresight on Mack Weldon’s part. Underwear that are made of good materials will eventually rub out a middle inseam.

There are also additional small inseams that you don’t really notice, but they are used to make the fabric contour to your body.

There are some downsides to their build quality though. If you look at one of the pictures of the inseams you can see that some of the inseams are very thick especially at the places where the fabric joins. You can feel these little joins after walking a full day. While they don’t cause chafing. They do cause noticeable discomfort.

Multi-layer waistband
Here is a shot of the legs outlining the additional spandex ring on the inside.
The extra attention to detail with the added mesh fabric (left), and the inseam that doesn’t go through the middle(right).
Here you can see the little divots that cause discomfort.
In these photos you can see the added small stitching for contours.
Here is a shot of the legs outlining the additional spandex ring on the inside.

Approximate Steps To Chafe

This is my completely fake measurement I made up of a quality of underwear. Since chafing is my primary issue. I have a Fitbit, and I took notes when chafing would kick in. This number isn’t scientific by any means. There are also a lot of variables, that could change this number. However, it’s the best I have, so deal with it.

These underwear have an ASTC rating of 18000+. My day ended with over 18 thousand steps with no chafing. The weather was in the eighties, and I was doing a fair amount of sweating as I always am. I had a morning walk, lunch walk, and then an afternoon walk, and the undies held up to all three, and kept going. They really are champs when it comes to chafing.

One thing to note though, that was out of the blue that happened some time later. Is on a different day I was out at a restaurant that was pretty hot on the inside with these on. After dinner when I stood up, and started walking there was noticeable chafe. This might be due to the fact that while you are sitting the underwear shouldn’t really have to do much.

Odor Control

One of the things that I don’t know if I am the only guy dealing with or if it just is never talked about between guys is odor between your legs. This can happen just while I sitting for long periods of time at work. I sit in a chair for 4–5 hours, and it is a moist area down there.

Swamp ass is real, and will sneak up on you. The second you turn around. There is damn swamp ass ready to ruin your day. Making you all self-conscious. Stupid swamp ass.

On a light note these have excellent odor control. After 18000+ these actually smelled better than the undershirt that I was wearing for the day. However, it wasn’t odorless much like the manufacture of XT2 talks about. The fabric manufacture claims that you won’t stink at all, and they still had a little odor to them at the end of the day. They sure aren’t going to stop a fart either. That odor is still coming out. If you are a gassy guy. These won’t be an answer to that problem. Crop dust with normal caution.

The gold standard in smell.

The Ride and Roll

For me, underwear can ride up or down in three different places. The inner top thighs, and the mid to lower thigh. Mid thighs if they are shorter, lower thigh if they are longer.

The XT2 ride down at the butt, and stay in place for the other two. They achieve staying in place at the thighs by the leg bands. The bands did work, but at a cost. Around step 8000 the bands start to become uncomfortable. They almost felt as though they were getting tighter around my thighs as the day went on. It’s more of a slight disappointment than anything else. The discomfort I felt with the bands is nothing compared to the chafe. If I have to take one or the other I will take the bands every time.

The problem that bothered me a little bit more is with them rolling down, and showing my butt crack. The ironic thing is that the manufacture says that they built the waistband specifically not to roll. The opposite happens for me. I couldn’t get them to stop rolling. I can image that for some people with a butt the waistband might work as advertised. My barrel shape says, “To hell with that!”

The barrel will give me problems every step of the way.


These are not cheap. At $34.00 a pair at time of writing these aren’t your value solution. They also aren’t checking all of my boxes that I need that perfect underwear to be.

Based on what I have read the average guy should have about 20 pairs of underwear. From what “they” say this will cover you for two weeks with some extra pairs in there for working out, or if you need a little refresher. That means that if you don’t buy a bunch at a discount. You are looking at close to $700 dollars to outfit yourself with these underwear.

I am still looking for that value solution. I think most guys would be OK with a couple pairs of underwear are high priced, but would still need to daily drivers that would fill out the fast majority of your wardrobe.


The XT2 are a really well built piece of underwear. However, for the price I don’t feel like they should be rolling anywhere. You are paying a premium for these underwear. For the price of these. I want every single one of my boxes checked. Unfortunately, for me these don’t do it. However, if you don’t care about your underwear rolling or, don’t have that problem with your underwear. You really just want to solve chafing and smells issues, and don’t care what you have to spend to get there these would be a good fit for you.

Comfort Diagram: You can see they still display my butt crack, and have a little discomfort around the legs.

Blog Notes and Links

This is the producer of the XT2 material used in the underwear.