Gear Review: Six Moon Designs Swift X Hiking Backpack

Six Moon Designs just dropped the Swift X Hiking Backpack. This is the 10-year anniversary edition of their original pack, and the modern updates will likely make this a legitimate competitor in the ever-evolving world of lightweight backpacking gear. Weighing between 1.5 and just over two pounds, the Swift X is highly customizable, with a variety of hip belt and shoulder strap configurations. It even has an optional delrin stay frame that is legitimately functional. 

Six Moon Designs Swift X At-a-Glance

The Swift X side compression straps are bright yellow, adding a little color and personality to the pack

The Swift X side compression straps are bright yellow, adding a little color and personality to the pack.

  • MSRP: $270 (regular straps) / $290 (vest)
  • Weight: 38 ounces
  • Volume: 45L (36 main body, 4L extension collar, 5L front and side pockets)
  • Maximum Weight Capacity: 35 pounds
  • Maximum Base Weight: 15 pounds
  • Pack Body Materials: LiteSkin LS07
  • Suggested Use: Lightweight/Long-Distance Backpacking

Circumstance of Review

I have taken this pack out on multiple weekend trips between late January and early May 2020. I have hiked through temperatures ranging from upper 30s to low 80s. All of my hiking has been done in Alabama in the Sipsey Wilderness and on the Pinhoti Trail in Talladega National Forest. I have experienced chilly winter mornings wearing this pack as well as sweaty exposed road walks. While the back cushion of the pack doesn’t exactly breathe, it is comfortable and I haven’t had any rubbing/irritation issues. The frame in the pack is about as efficient as you could hope for in a lightweight pack like this, legitimately transferring weight off the shoulders and onto the hips.

The vest system is the most unique and for me, most comfortable feature of the pack. There are two straps that buckle across the sternum, allowing for even distribution of pressure points on the chest. There are also an abundance of pockets on the vest that make for efficient organization of snacks, earbuds, and other little handy trinkets you want to access throughout the day.

Swift X Features

The handy little zippered stash pocket near the top of the inside of the pack is awesome for keeping knickknacks you want to keep easy access to.

  • Two shoulder strap style options
    • Shoulder Harness (traditional straps with built-in whistle on sternum strap buckle)
    • Vest Harness (multiple pockets on each strap and dual sternum straps)
  • Two different shoulder strap/vest sizes that are also each adjustable
  • Unique “inverted” shoulder strap adjustment system
  • Load lifters on the shoulder straps
  • Three exterior woven pockets (two side, one rear)
  • All pockets feature breathable and durable four-way stretch material 
  • Large shoulder strap pockets on both styles of straps
  • Removable hip belt (comes in three different sizes)
  • Hip belt features two adjustment straps (top and bottom) on each side
  • Minimal contact back panel
  • Top loading with dry bag closure
  • Internal zippered stash pocket
  • Multiple point cord compression system (on sides)
  • Single ice axe or trekking pole attachment point
  • Dual hydration ports
  • Removable bag to hold hydration bladder
  • Removable Delrin hoop stay (frame)


For the most part, this is a pretty standard pack as far as comfort goes. The cushioned back panel is soft, but still gets hot and sweaty. The side pockets are standard. The hip belt’s two adjustment straps on each side are pretty standard. What makes this pack notably comfortable are two features: the vest yoke shoulder strap system and unique shoulder strap adjustment system.

Flight Vest Yoke

Ever since testing Mountainsmith’s Zerk 40, I have been a fan of beefy shoulder straps. I like the numerous accessible pockets this provides, as well as more surface area to distribute weight across the chest. The vest system on this pack does both of those things extremely well, and it takes it a step further by having two sternum straps, which is a big deal. One strap buckles right around the collarbone while the second strap buckles 6-8 inches below. In almost every pack I’ve worn before, I get pretty close to chafing around where the sternum strap buckles, but I’ve liked the close fit that it provides. By having two of these straps, the weight distribution allows the user to be securely strapped into the pack without a hint of chafing. The straps are also thin material with a good width, which helps with weight distribution. 

I use the outer mesh vest pocket to store my camera case. There’s even a little plastic loop on the pack to attach the back of the case.

Each strap has three pockets, making a total of six pockets conveniently placed for your snackage and phone storage. While I’ll admit that it is difficult to take advantage of all three pockets on each side at once, the combination of options is still super handy. You can easily put your phone and a few snacks on one side while still having the mesh pocket available for trash. There is even a pocket on each side large enough to hold a SmartWater bottle, so if you’re a front water carrier, this pack gets extra points.

Shoulder Strap Adjustment System

The shoulder strap adjustment configuration on this pack is unique and quite possibly a breakthrough in pack comfort technology. I’ll do my best here to put this system into words, but I think the picture below will be the most handy in deciphering its functionality.

The top of the straps are routinely attached, nothing fancy here (other than the fact that this pack has load lifters). Below, each strap is attached to move freely on a piece of webbing attached at the center and bottom of the pack. In order to adjust the straps, you pull up on the bottom webbing, cinching the straps tighter against your body. Once adjusted snugly, the bottom of the shoulder straps can still move freely, meaning that they adjust as your body contorts and moves along the trail. This constantly adjusts to redistribute the weight between your shoulders. Now, it isn’t perfect, and doesn’t always keep the weight exactly even, but it does make it a lot more difficult for a majority of the weight to shift to one shoulder. This strap system creates a dynamic fit that, along with the dual sternum straps, makes for a unique and prime fit as you work your way up or down any trail.

Finally, to read more about the health benefits of the vest harness, check it out here under the “suspension” tab.

Did I Like It?

The shoulder straps/vest Velcro into place in one of the four attachment pockets.

Definitely. This pack is awesome. The vest system on this harness is by far the best feature, and frankly it’s probably a mistake not to get it and go with the standard shoulder straps. The Swift X is different in a really good way. It isn’t the lightest pack out there, but it’s still a great middle-of-the-road weight for a lightweight setup that will leave hikers feeling good when they roll out of town loaded to the gills with a resupply. The hip belt is great if you want it, but if you don’t like hip belts, I think the vest system is the best option for packs without a hip bet. 


  • The vest system on this pack is sweet. It makes the pack uniquely comfortable and also has excellently efficient pockets.
  • The small interior zip pocket is great for thru-hikers to keep electronics and wallet in a place that is highly water resistant and easy to access when you get to an ice cream shop at the end of the day.
  • The optional hip belt on this pack is a legitimate hip belt. Typically, an optional hip belt is a piece of webbing with buckles. The hip belt on this pack is as good as you could expect on any lightweight backpack with a decent-sized pocket on each and good adjustability. Since there is a frame inside this pack that runs all the way down to the base, the hip belt actually transfers weight to the hips. Basically, it’s a real hip belt if you want it, and it’s easy to remove if you don’t.
  • Everything else about the pack is solid standard configuration for a lightweight backpack: roll top, good stretchy pockets on the sides and front, and a water resistant pack body.


  • Though the pack is highly adjustable, it also makes for a lot of straps flopping around.
  • The roll top closure does NOT buckle on the sides of the pack. The only way to close the pack is to buckle the sides of the roll top to themselves. Most packs offer both options and I definitely prefer being able to cinch the top down to the sides for a more streamlined configuration.
  • This pack is on the pricey side. It’s reasonable for the quality, but it’s not exactly a bargain buy.

Final Thoughts

The Swift X is a unique innovative pack that should be on any gear junkie’s radar. If you’re looking at all the options out there, this one should be on the list because it is made to carry differently by a guy trying to figure out how to hike comfortably after a bout with cancer. Move over Lunar Solo: SMD may just have a new #1 piece of gear.

Shop the SMD Swift X Here

Comparable Packs

Gossamer Gear G4-20
MSRP: $180
Weight: 25oz

Zpacks Arc Haul
MSRP: $299
Weight: 23oz

Mountainsmith Zerk 40
MSRP: $219.95
Weight: 28oz

**This product was donated for purpose of review

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