Mountain Hardwear Quantum 3D
1st Dimension Sleeping Bag

I’ve been spending as much time outdoors as possible for as long as I can remember. I tend to gravitate towards all manner of outdoor recreation with hiking, camping, backpacking, and mountain biking topping off the list. I’ve been camping all my life, summer vacation as a kid was a weeks worth of car camping at the beach.  Friends of my parents used to take us hiking in the mountains with an occasional overnight trip. Since then I’ve been hooked. I’ll hike or camp in any weather, in any season. That can range from 10 below zero in the snow to 100 plus heat. That’s the beauty of living in New England. I also have a gear addiction. I need gear. All Kinds, any kind.

This is the first mummy bag I’ve owned, so I’ve got nothing really to compare it too. I was initially attracted to the MH bags because I worked at a shop that sold them. And, the price was right, so I couldn’t argue. I decided on the 1st Dimension because of the 30dF rating and the Polarguard 3D insulation. I figured the temp rating would fall in the middle of what I planned on using it for, mostly a three-season bag, with a few winter camping trips thrown in.

The first time I used the bag was in the end of July. I’ll admit, I didn’t need a 30d bag in July, but it was new & I couldn’t leave it home! That night wasn’t extremely hot, but I sweat a lot! I’m a hot sleeper to begin with, so I slept on top of it the rest of the night. Another trip we took was in late September, temp’s quite a bit cooler, roughly in the low 50’s, and I still had to sleep with it unzipped. I’m eager to see what it’ll do in the winter. Based on what I’ve heard, some companies will pad or fake their temp ratings, or test under “controlled” conditions. But, from what I’ve seen thus far, this bag should keep me nice & toasty.

The 1st Dimension has the usual smattering of features like the hood with one handed draw cord, draft tubes at the neck and down the zipper, and Velcro tab at the top of the zipper. It also comes with a stuff sack and cotton storage sack. This bag also has a feature that I haven’t seen before. They call it the “Quantum Expander”. To quote the website:

"The Quantum Expander is an oversized, expandable draft tube operated by a second zipper parallel to the bag's entry zipper. Opening or closing the Expander's zipper allows you to adjust the bag's volume, adding up to eight inches in girth when fully expanded. In warmer conditions when some extra space and ventilation would be great, unzip the Quantum Expander. When it's cold, zip it up and you've got your most efficient heat retention. And, when you're on a high-altitude expedition where you need to wear a down suit to bed, you can again unzip the Expander and fit comfortably into your bag. What's more, you can also adjust the Expander's double-slider zipper to strategically localize the expansion in, say, just the shoulder area, or the knees, or the feet. In short, the Expander allows one bag to perform like many different bags." End Quote

The fit of this bag is great for me, and I don’t have a problem feeling confined in mummy style bags. So, the Quantum expander may not matter to some, as it will allow for cold spots when open, as the web site says.

So, in summary, if you want a bag that will work well in most cases, I don’t think there is such a thing. But, the MH 1st Dimension bag works well for what it’s intended for. The Polarguard 3D compresses well, retains its loft, and keeps you warm even if it gets wet. And with a $160 price tag, you can afford to buy warmer and cooler weather bags.