Mystery Ranch is one of those companies that needs no introduction at this point, if you are unfamiliar with them please refer to any of the reviews on this site covering their other bags. With myself being one of the newer reviewers at The Perfect Pack it surprised me that nobody has reviewed the Mystery Ranch Three Day Assault Pack (3DAP) yet. It’s definitely one of the company’s most popular packs amongst both the military members and EDC Gurus in our community.
Before we get into this review I would like to preface that the 3DAP that I am using for this review was bought by myself and not provided to us by Mystery Ranch. I would also like to note that my pack is of an older generation than those on sale at time of writing. The manufacturing listed on the tag says 2008 so take this review with a pinch of salt as some materials and features may have been changed and improved upon since this bag was made. If anyone reading this review notes clear differences on their newer 3DAP, please comment below, I’d like to know what has changed in the design in the last 12 years.

Quality and Comfort
The 3DAP is the flagship pack for the Military line of Mystery Ranch bags. It is an incredibly versatile bag and well-proven for both conventional and special military operations. I personally have seen everyone from Army infantrymen to Air Force Combat Controllers utilize this bag for multi-day tastings or infilling to an objective via airborne operations. Donning the 3DAP for the first time, I ceased to wonder why so many military groups choose this pack. Like all other Mystery Ranch bags, the 3DAP’s quality is second to none. The heavy-duty stitching and oversized zippers make sure that this bag won’t come apart on you without a damn good reason. Being built from all 500D Cordura helps meet a good balance between being lightweight and durable.

In my experience, most military-focused bags sacrifice comfort over functionality, and there is nothing wrong with that, but when the users are going to have 45 plus pounds on their backs for multiple hours, it pays to have something a little more comfortable. This is an area where the 3DAP outshines most of its competition. Featuring an adjustable yoke for shorter and taller users, you can adjust the height of the bag in a matter of minutes. All you need to do is remove the plastic back panel, use the panel as a divider for the fully-velcroed yoke and you can then raise or lower the yoke to fit your back. I wish more packs included a simple system like this on their larger bags.
My only issue with this system is that I could not lower the yoke far enough down to have the belt meet my waist (and I’m only five foot nine). This was very disappointing to be honest. The belt tucks into compartments beneath the water bottle pockets when not in use, so most of my time using this pack I would fully collapse the yoke to keep the bag high on my back. The belt is very underwhelming on a bag at this price point (this may have been fixed already), with virtually no padding at all. With a little digging, it’s possible to acquire a set of Mystery Ranch Live Wings for extra padding, but I think they should have come with the bag in the first place. Unfortunately, I did not have a set of them for this review.

Now that the bad is out of the way let’s talk about the good, and there is a lot of it to go over on this bag. The Yoke is incredibly comfortable! To date, I’ve yet to use a system this comfortable. The padded shoulder straps are wide and covered in a breathable mesh on the inside to reduce heat buildup. The same can be said about the padded back panel. The sternum strap is adjustable and in a great location although it has no keeper for the extra strap that hangs off of it once adjusted. Like most hiking and military-style rucksacks, there are multiple ways to adjust the bag to contour to your back. Load-lifter straps on the top bring the bag closer or further from the shoulders with waist-belt adjustments to more evenly distribute the load of the bag onto the hips. All of these adjustment straps include keepers for the slack ends, which I like. With light-to-medium loads this pack honestly feels like it’s floating on my back, when properly adjusted, and that’s something I can’t say about many other bags on the market.

Organization
Coming in at a decent 32 Litres, the 3-Day Assault Pack also has plenty of room for all your items. While Mystery Ranch markets the 3DAP as a 72-hour bag, from my personal experience I don’t think it’s big enough to fit this role. If you’re talking about just taking three days’ worth of clothes and snacks, with no shelter system or extra equipment, then I can see it working but, to me, 32 litres is simply not enough room.
The exterior of the bag has side PALS webbing which provides (much needed, in my opinion) lash-on expansion to carry capacity. There are also front daisy chains on the front of the pack running vertically. I found these to be a nice addition and I appreciate that Mystery Ranch didn’t cover the entire face of the pack with them as they would have been overkill. Weaving in between the daisy chains are two horizontal compression straps to minimize bulk when the pack isn’t fully loaded

Moving down we have two side water bottle pockets with drain holes. Not much to report here except they have an elastic band around the opening so to keep them closed when not in use. Very useful for keeping the bag for snagging on doorways or tree branches. I used these to support my tripod, to good effect, with the compression straps stabilizing the long item on the side of the pack.
All of Mystery Ranch’s features are brought together with the signature 3-Zip design, providing ready access to the pack’s contents. This is certainly one of the bag’s more unique features and it allows the user multiple ways to get into different parts of their bag without moving everything around, like in traditional backpacks. There is nothing worse than fishing for a small item on the bottom of a top-loader pack. With the 3-Zip design, you only need to pull the main zipper to its bottom-most point and leave the other two zippers in place. This should give access to the bottom without everything falling out.

At the very top of the pack, there are two small admin style pockets. The lower is considerably larger than the upper, with a mesh bottom while the top one has internal organization slots for pens, wallets, and even M&Ms.

Moving to the interior of the bag there is a lot to talk about. On the interior sidewalls, there are two internal zip mesh pockets with a flow-through backing. These are in a great location and very easy to access, the mesh is also very well constructed and will not easily rip.
Next to the Mesh pockets, there are two tall, internal drop-in pockets, that are perfect for placing a water bottle or extra layer into. Think of them as an open stuff sack sewn into the wall of the pack. I could throw a specific item in them and know that it will stay separated from everything else, making it infinitely easier to find said item.

The back of the pack has a reinforced wall lined with very tight PALS webbing: this is a nice feature for sure but I found very limited use of this webbing. The one time I did use them was to secure a 35-pound plate to the interior of the pack. Not only did this work incredibly well, keeping the weight right against my back, but it also held tight after a full 19-mile ruck march. After removing the weight from the PALS webbing I was amazed to see that the stitching was fulling intact with no frays. If this does not speak to the quality of the bag, then I don’t know what does.

The next pocket in the pack confused me for the longest time. Right below the interior PALS webbing, there is a 6” X 3” pocket with two sets of compression straps above it. At first, I thought it was a place to fix a large radio system but I’m sure that you could use it for for holding a rifle. I would place the buttstock of the weapon into the pocket and then strap it down with the compression straps, then stick the remaining part of the rifle through the broad top zip. I don’t believe the modern versions of the 3DAP come with this feature and I can understand why most people will never use it, since it will mostly just be in their way if they are trying to store a laptop in the bag. That being said it’s still a noteworthy feature.
Whats Perfect
- 500D and build quality is second to none.
- Built-in America
- Lifetime warranty
- Very comfortable padded shoulder straps with adjustable harness
- Well suited to carry large tripods or firearms
What’s Not
- Pricy, But this kind of quality doesn’t come cheap
- Cheap waist-belt
- Mis-Marketed, not big enough for 72 hours of sustainment in my opinion

Wrap Up
All in all the Three Day Assault Pack by Mystery Ranch is a kick-ass, built in America, gear hauler. This pack is extremely capable for almost any outdoor adventure whether it be a day at the range, an overnight hiking, or a busy day in the city, the 3DAP will not let you down.
Disclaimer: The 3-Day Assault Pack was purchased privately and subsequently used for this review. The contents of this review were not discussed with Mystery Ranch prior to publication. Our reviews are unbiased and never adjusted to keep a brand happy.