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Reviews > Packs > Internal and External Framed Backpacks > Black Diamond Mercury 75 pack > Test Report by Justin Potts

December 10, 2012



NAME: Justin Potts
AGE: 22
LOCATION: Sapulpa, Oklahoma, USA
HEIGHT: 5' 8" (1.73 m)
WEIGHT: 180 lb (81.60 kg)

When introduced to the backpacking community I immediately fell in love with it, and I fell hard! Not a weekend goes by that I am not out in the wilderness somewhere. I have roughly 2,000 mi (3220 km) of hiking/backpacking experience mostly in Oklahoma's Wichita Wildlife Refuge. I like to pack light, with a base weight of 15 lbs (6.8 kg) but I also like to be comfortable. I hike hard and fast to reach a destination, and explore after I make camp. I shall see what this turns into as I keep backpacking.



Manufacturer: Black Diamond Equipment, Ltd.
Year of Manufacture: 2012
Manufacturer's Website:
Product: Mercury Pack
MSRP: 279.95 USD
Size Tested: Medium
Specifications for Size Medium
Listed Weight: 4 lb 12 oz (2,180 g)
Actual Weight: 4 lb 11 oz (2,130 g)
Volume: 4,577 cu in (75L)
Torso Size: 17.5-20.5 in (45-52 cm)
Waist Size: 29- 34 in (73-86 cm)
Color: Stone (also available in Coal)

Product Description

The Black Diamond Mercury pack (hereafter referred to as Mercury or the pack) is a top-loading/panel-loading pack with a floating lid designed by Black Diamond for use on long-distance extended multi-week trips. The manufacturer uses an "ergoACTIV XP suspension system uses a custom, 3D pivoting hipbelt with urethane tendons, a men's-specific fit and SwingArm shoulder straps for increased stability and dynamic load transfer" to provide maximum comfort and mobility on such extended trips.

By visiting the Black Diamond website I was able to gather a fairly good idea of what I was going to be receiving. Never having used a Black Diamond pack before, the Mercury was what I expected as far as design and build.

The pack was packaged in the typical backpack fashion (wrapped in a clear plastic bag. After freeing it from this plastic cage I noticed that the hipbelt was not attached, rather just wrapped around the pack. No big deal, just have to attach the hipbelt right? Sort of... After several minutes of head scratching and trying to just put the peg in the hole I decided it was not going to work. So I referred to the owner's manual/instruction booklet. That should tell me how... No such luck. It has a small picture of an Allen wrench. I eventually found an Allen wrench inside the hipbelt pocket held by a convenient loop. The wrench is used to remove a bolt at the ergoACTIV XP ball joint in the middle lower section of the pack. Done! Luckily adjusting the torso length was fairly easy. While attaching the hipbelt I accidentally adjusted the torso. The hipbelt slides up and down by loosening and then tightening the ball joint previously mentioned to adjust the length. This worries me because this pack is designed for heavy loads on long-distance days. So I will be keeping a close watch on whether the weight of the pack causes this joint to slide down after adjusted. Also, this now means that this Allen wrench must accompany me and not be lost on all trips, just in case adjustments need to be made. Not an exciting feature.

Enough, onto the pack. The Mercury is a top-loading/panel-loading pack meaning that it has the traditional drawstring collar at the top, and also opens along the majority of the face of the pack by means of a heavy duty zipper. This means that it can be laid down and unzipped to reveal the inside of the majority of the pack (pictured below). Unfolding this flap reveals two mesh zippered pockets for organization (also pictured). And on the outside of the flap is an exterior pocket that runs down the majority of the flap, also closed with a heavy duty zipper. Almost all of the zippers on the pack are heavy duty and waterproofed with polyurethane (the orange seams pictured, that I originally thought was just decorative piping after viewing the website). But this typically makes zippers tricky and stiff, and the Mercury is no exception.


At the top of the pack is a floating top pocket with a waterproof zip pocket on top and a traditional zippered pocket underneath the lid (pictured below). The lid can also be removed and used as a hip pack, with the provided strap, for short day adventures away from camp. The hipbelt has one zippered pocket on each side for quick grab items (ChapStick, compass, small snacks etc.). And finally finishing up the pocket department are two stretch side pockets, one on each side. The only nitpick I have with the pockets is that the bottom side compression strap runs across the mesh pockets which may make it difficult to get items in and out. I will be reporting back my findings in the Field Report section.

As far as materials go the pack is fabricated from 400d polyester twill, and 420d nylon twill. It all feels extremely heavy duty, but I can not tell what parts are polyester vs nylon.

There is only one tool loop with corresponding bungee to attach trekking poles. I do not know if was by accident or if it was specifically designed this way, but the loop and bungee are both located on the flap which gives access to the exterior pocket and the front loading panel without removing stowed trekking poles.

Inside the pack is a sleeve for a hydration bladder. There is a hook at the top of this pouch to attach hydration bladders. The sleeve fits my 3 L bladder and has enough room to put another bladder in the sleeve if I were so inclined to do so. There are drink tube ports on each side just above the shoulder straps. The tube can be routed through a port and attached to the shoulder strap via a formed plastic hook.

Finally on to the mysterious suspension system. I say mysterious because there is very little literature on any of the key features. First up is the hipbelt, it is big, stiff, padded, bulky, and strong. Normally this would sound awful, only this pack is designed to carry 50+ lb (23 kg) and do so comfortably, so I would not trade it for anything. I walked around the house in the pack carrying 60 lb (27 kg) and it was still extremely comfortable. The hip-belt has breathable mesh over a very dense foam with a stiffer pad in the lumbar area, which makes it feel supportive. The ergoACTIV XP ball joint is designed to give "unparalleled freedom of movement", I shall see about that, this seems like it would be hard to guarantee with a pack this size. So far so good, but I will be discussing it further in the Field Report after I get it out on some trails for a couple of weeks worth of packing. The hipbelt is secured with a typical quick release buckle, and the cinch strap is V shaped to provide even distribution through the belt. And finally there is a strap on each side of the hipbelt that attaches to the pack. When these straps are tightened it restricts the "freedom of movement". Not quite sure why these would be necessary on a pack that boasts about "unparalleled freedom of movement", again to be determined and reported in the Field Report Section.

The other feature of the suspension system is the SwingArm shoulder straps. The straps are fairly padded and comfortable, but the interesting feature is the "SwingArm." To create freedom of movement the straps actually move with the body. To do this by being tethered together via a steel cable. At the point where the strap straps attach to the pack, there is a small sleeve concealing the cable which runs through the pack to the other side where it is attached to the other strap. This cable allows a bit of a rocking action, roughly 2 in (5 cm), by allowing one strap to go up while the other goes down. This feature interests me, but I do not know much more about how it works just yet. I will be reporting more details later in the Field Report.

Closing Statement

All told I am stoked about this pack. I am excited to get it out and start testing as soon as possible!

This concludes the Initial Report section.



I have used this pack on two different trips:

First, a 15-day, 14-night trip in the Sangre De Cristo Mountains in late summer. Elevation ~13,000 ft (4,000 m) with somewhere around 5,300 ft (1,600 m) gain from the base. Covering somewhere between 10-12 mi (16-19 km) a day. Here it also rained every day at 4-6 PM like clockwork.

Second, a three-night backpacking trip in the Wichita Wildlife Refuge in September. We covered roughly 5 mi (8 km) per day. The terrain was relatively flat, and it rained hard all four days/three nights. It would probably be best described as a swamp trudge vs. a backpacking trip...


To start things off, I was a little leery on being able to completely fill this pack before winter backpacking. As it turns out, I cannot, even with all of my gear and food for the two weeks in Colorado, I filled the pack body but did not have to use the extension collar. On a side note related to packing, the internal organization pockets keep everything neat and clean on the trail.

On the two week trip in Colorado I was carrying about 50 lb (23 kg) at the beginning. The pack was remarkably comfortable even with such a heavy load. For reference I generally carry less than 30 lb (14 kg) in a lightweight internal frame pack.

Next, I could not get over the suspension. The ergoACTIV hipbelt does take a little bit getting used to, and some tinkering to get it adjusted just right. After it is set, it is extremely comfortable! The ergoACTIV hipbelt keeps the pack body centered on my spine and not sway back and forth as my hips moved up and down through a stride. On the other hand the SwingArm shoulder straps did have one minor issue. I like that the straps move, keeping even pressure on my shoulders. However, I did notice that if I did not have the pack up quite high enough the pack would pinch the love handle region of my back between the hipbelt and shoulder strap.

The last thing I would like to point out is that this pack handles the rain fantastically. I cannot find anything that says it actually is waterproof, but the waterproof zippers make me think that it might be. Plus in all of the rain I encountered while testing this pack there was no measurable amount of moisture inside the pack (except a water bladder malfunction, but that is a different story).


The pack is still in excellent condition. It carries a heavy load quite well, which to me is important in a large capacity pack. Aside from a few scuffs, there are no signs of weakening fabric or seams. The waterproof zippers have loosened up some making them easier to operate. And the pack still has 100% functionality.

This concludes my Field Report section. Please check back in a couple of months for my Long Term Report. I would like to thank Black Diamond and for providing me with this testing opportunity.



It is easily discernible throughout my test series and reviews that I spend the majority of my time backpacking in the Wichita Wildlife Refuge here in southwest Oklahoma, USA. The last two months testing this pack was no exception. I managed to get it out on three separate two-night hiking/climbing trips because the weather has been abnormally amazing. On these nine days in November and December the highs were in the mid 70's F (low 20's C) and the lows were in the high 40's F (~8 C) at night. So with weather like this, this late in the year, of course I had to get out in it as much as I could. We were climbing most of the time, so we only covered around 4 mi (6.5 km) a day.

Here It is in action, reaching the lake.
Also makes for a good recliner waiting out a rain shower.


The Mercury 75L is by far the largest pack that I have ever used. The capacity of this thing is outstanding and continues to amaze me every-time I pull it out to get ready for a trip. I would not call myself a super lightweight backpacker, but my gear tends to be relatively small and compact. For perspective, before starting this test series my backpack of choice had a capacity of 58L, and still had some room to play with.

That being said, I've had trouble filling this pack to capacity so on these three trips I enlisted the help of my girlfriend. On these trips my pack load consisted of the basic backpacking gear (tent, sleep system, cookset, stove, food, water etc...) for myself and my girlfriend, as well as all of our climbing gear, while she carried the rope attached to a small hydration pack. (I cannot help but to think she got the gold mine and I got the shaft on these trips). Needless to say, I finally filled this pack completely.

While the pack was undoubtedly heavy carrying such a large amount of gear, it was designed to carry heavy loads comfortably... And it does carry heavy loads relatively comfortably. I think that it would be silly to think that carrying any pack weighing this much would be 100% comfortable, but compared to other packs I have the Mercury 75L is very comfortable, even carrying loads up to 65 lb (29.5 kg). Now that being said, the manufacturer's website lists the recommended usage at 50 lb (23 kg). Which for my intended purpose for these 3 trips meant the pack was about two-thirds full, so I went ahead and filled the pack just to see how it would handle a load that exceeded its recommendation. And the result was that it can do so just fine.


Aside from the initial confusion, which was caused partly by poor design and partly by lack of instructions on how to attach the hipbelt to the pack (which is mentioned in the Initial Report) I do not have a lot to criticize. Which saddens me because it is much easier to remain objective when there is a dislike here and there. Perhaps I will mention that the sheer volume of this pack is slightly excessive for my uses. Mostly because winters here in Oklahoma are not incredibly cold, so I do not require very much bulky cold weather gear. even I will continue to use this pack when I take my niece and nephews out because they are still a bit too young and small to be able to carry all of their own gear and still be able to enjoy backpacking. Other than that, I cannot foresee another time that I will get this pack close to full.

On the other hand, I cannot express through this report how truly comfortable the ergoACTIV XP suspension system actually is. It does take a little bit of time, patience, and tinkering to get it set properly. After that however it is good to go. It has become my favorite suspension system by far. And finally the ergoACTIV XP suspension coupled with the SwingArm shoulder straps make this pack truly 'forgetable' (in the sense that I literally forget I am wearing a pack sometimes).

Final Comments

I have really enjoyed testing this pack. I would like to thank Black Diamond and for providing me with this testing opportunity.

See you down the trail. ;-)

This report was created with the Report Writer Version 1. Copyright 2012. All rights reserved.

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