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  • Unique welded construction reduces weight and bulk, maximizes insulation loft, eliminates cold spots and thermally maps insulation to areas where warmth is needed most
  • Thermal.Q insulation has outstanding compressibility, maintains excellent loft and continues to insulate even when damp
  • Comfort mummy cut maximizes warmth and fit while minimizing weight
  • Ergonomic draft collar and tailored hood with face gasket comfortably block drafts and seal in warmth
  • Comfort footbox follows natural foot position for maximum warmth and comfort
  • Soft polyester lining wicks away moisture and lightweight nylon shell has a durable water repellent finish to ward off moisture
  • Full-length #5 zipper with double sliders for versatile ventilation
  • Zippered pocket at shoulder
  • Nylon compression stuff sack and mesh storage bag included
  • 34³F EN (European Norm) lower-limit rating is suitable for 3-season use


View all Mountain Hardwear Men's Sleeping Bags

REI membership


Best Use Backpacking
EN Lower Limit 34 degrees Fahrenheit
EN Comfort 42 degrees Fahrenheit
Temperature Rating (F) 34 degrees Fahrenheit
Temperature Rating (C) 1 degrees Celsius
Long Left
2 lbs. 3 oz. ounces
Regular Left
2 lbs. 1 oz. ounces
Shell 30-denier ripstop nylon
Zipper Location Left
Insulation Type Synthetic
Fill Thermal.Q synthetic fibers
Fill Weight 1 lb. 4 oz.
Lining 40-denier polyester taffeta
Sleeping Bag Shape Mummy
Fits Up To (in.)
Long Left
78 inches
Regular Left
72 inches
Shoulder Girth (in.)
Long Left
65 inches
Regular Left
63 inches
Hip Girth (in.)
Long Left
64 inches
Regular Left
59 inches
Stuff Sack Size 6 x 12 inches
Stuff Sack Volume
Long Left
7 liters
Regular Left
7 liters
Compressed Volume
Long Left
5.4 liters
Regular Left
5 liters
Gender Unisex
Rated 5 out of 5 by from True to specs, great warmth for weight Brought this bag for backpacking in Rocky Mountain National Park, extremely happy with my purchase! Slept warm and sound in a t-shirt and shorts at 11,050 ft on an UNinsulated sleeping pad. I am 6'1, bought the long bag and found the torso and foot box both very roomy. This is my first mummy bag as I am a stomach/side sleeper and I had no issues moving around inside the bag or getting it to roll with me. The second zipper at the bag's bottom is nice if you get warm and want to pop a leg out.
Date published: 2016-08-12
Rated 5 out of 5 by from First Impressions Nice well made bag. Nice footbox and hood, reasonably roomy mummy. I am 6' 185 lbs. and could just get into the regular. The long was more comfortable and spacious for me, I opted for the extra two oz. My long weighs 2lb 5oz, 2 oz more than the specs show, no biggie. Without much effort it goes to 7x11 inches in the provided compression sack. Overall 2lb 8oz, a nysilk stuff sack would cut that 2oz. Comes with a nice storage sack too. The big question will be how it performs around 32F, 0C. I haven't used it yet in that condition. The Z Flame may be an equally good choice, but about 11oz more and more bulk. I wanted a bag for summer, but probably am pushing it a bit for the high Sierras, where getting to freezing at night does happen in July and Aug. But I saw a few reviews that were favorable for performance at 30F.
Date published: 2015-05-23
Rated 5 out of 5 by from Worth every penny Bought this bag on a whim. My buddy and I were on a camping/road trip from southern CA in May. We had originally planned to go to Zion and Escelante in Southern Utah. During the trip he changed his mind and wanted to go backpacking into the mountains, so we decided to head to the High Uintas, Ut. I only packed for warmer temperatures so we stopped at REI in Salt Lake City so I could get a few things. Being a unplanned expense I wanted a bag I could take into the high mountains and colder temperatures without breaking the bank. I did a little research on bags and found this one to be the best bang for the buck! I was so happy and pleased with the purchase. We had planned to stay in the mountains for 3 days/nights but after 2 my friend had enough because he was freezing with his 45 degree bag. The temperature dropped into the low 30's upper 20's on us with rain and snow while we were out. The bag preformed beyond my expectations and I was comfortable and slept well despite the freezing conditions we found ourselves in. Later on the trip we planned to cut over through Nevada and hit the eastern Sierra's and Sequoia Nat Park. He made an emergency stop at REI and bought the same bag for the same reasons. Again the temps were low 30's and we were both extremely pleased with the bags performance. It packs up small, and does a phenomenal job at repealing moister, and cold. I look forward to many trips and years of use out of this bag!!
Date published: 2016-07-27
Rated 4 out of 5 by from Initial Impressions - Long size I just picked up the Spark at a great price during the Anniversary Sale (it pays to be a Member!) and though I haven't used it in the field I have a few initial impressions that might be helpful for any potential buyers of the Spark. I will be base camping in the rockies in a week, so I will update on its performance later. It does have a nice fluffy loft to it, so I feel confident that it will perform well close to its 34F lower limit rating. I own a down bag that is lighter and warmer than the spark, but after reading the specs and a couple field reviews on the Lamina, decided it wouldn't be a bad a idea to have a bag that would work well in slightly warmer weather, didn't have to fuss too much about getting wet, and otherwise handle with kid gloves. A rough-and-tumble bag, if you will. The weight and compressed size listed in the specs are what initially caught my attention. Sadly, either MHW seems to have fudged their numbers a bit, or there is just a wide margin of variance in the manufacturing process. The long size, which I purchased, is supposed to weight in at 2 lbs 3oz, and pack down to 6" x 12" in the compression sack. The included compression sack has a little tag that states that it is a 7" x 12", but even when I have it packed in there good, it is still a bit bulkier than advertised at about 8" x 13." I realize that the weight specs for sleeping bags generally do not account for the compression sack, but on my digital scale, the whole kit-n-kaboodle weighs in at 40.65 oz, or almost 2 lbs, 9 oz. The compression sack itself only weighs 2.25 oz, so conservatively, the Spark weighs a good 3 oz more than advertised. Not a big deal for me, however as I plan to keep the bag regardless. Ounce-counters should consider themselves forewarned. For a synthetic with temp specs, its size and weight are satisfactory, but there might be others pickier than me.
Date published: 2015-05-18
Rated 5 out of 5 by from Great bag for backpacking. I have used this bag in the summer and in fall nights as cold as 18degree, which was a little cold for this bag. My favorite feature of this bag is its size and weight. It packs very small and is light.
Date published: 2016-01-09
Rated 5 out of 5 by from Could have slept in the nude... Picked this up last week and took it up to Kings Canyon. At 10,000 ft, the temps dropped to the mid 30's at night, but this sucker kept me warm and fuzzy. Best part - packs really small into included compression sack, so no more grumpily shoving a bulky sleeping bag into my pack. Only thing i'd improve is the zipper, darn thing gets stuck if you don't zip it just right, but hey, its better than freezing. Excellent bag for the price.
Date published: 2016-09-09
Rated 5 out of 5 by from Great compact synthetic bag! This is a great synthetic bag for backpacking! Very compact and warm. I felt very comfortable in very low temperatures (~30*F). This is a mummy bag, though, so if you need some wiggle room, it may not be the best for you.
Date published: 2016-05-02
Rated 5 out of 5 by from An excellent, lightweight sleeping bag! I bought this for my son for backpack camping. He loves it! It is just right for cold or warm camping.
Date published: 2016-09-18
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Can you zip this together with another sleeping bag? My wife doesn't like it unless it zips up two! Any suggestions if not? Would like a bag with similar qualities to this one (three-season), but with the option of going solo or duo zipped to another bag.

Asked by: Aaron at Camp
Yes, the Lamina Z Spark can be mated with another sleeping bag that has a right handed zipper and the same zipper coil number. The Laminina Z Spark Sleeping Bag - Women's would be the best choice. It has the same EN temperature rating, zipper coil and insulation.
Answered by: REIservice
Date published: 2017-06-08

Are there any other differences between Lamina Z Spark and the HyperLamina Spark 35, aside from the centre-zip ?

Asked by: mattsev
The HyperLamina Spark model does have a completely different zipper system. It is also lighter in weight compared to the Lamina Z Spark.
Answered by: REIservice
Date published: 2017-04-01

Is there a footbox zipper?

Asked by: CAbrowNbpkr
​No, there is not a zipper at the footbox.
Answered by: REIservice
Date published: 2017-01-15

Is this a children's sleeping bag?

Asked by: Goony
The Mountain Hardwear Lamina Z Spark Sleeping Bag is sized for adults.
Answered by: REIservice
Date published: 2017-04-01
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