Therm-a-Rest Parsec 0
The Parsec 0 provides impressive comfort and warmth for winter backpacking, with a nearly unbeatable low weight for a 0F bag. That hard-to-match combination kept me warm and my backpack light during overnight winter hikes.
Therm-a-Rest Parsec 0 Specs
MSRP: $529.95, small; $569.95, regular; $619.95, long
Weight: Small, 2 pounds, 2 ounces; regular, 2 pounds, 6 ounces; long, 2 pounds, 9 ounces
Outer Shell: 100% recycled nylon ripstop with durable water repellent (DWR) coating
Temperature Rating: Comfortable for sleeping to 14F; 0F is the lowest safe temperature.
Insulation: 800 fill goose Nikwax Hydrophobic Down RDS (translation: water resistant down that follows the Responsible Down Standard certifying that waterfowl in the down supply chain are treated humanely).
About the Parsec 0
The Parsec 0 strikes a great balance of weight, warmth, and comfort. I carried it in my backpack for overnight trips when the temperatures ranged from the 20s to 1F, and slept warm and comfortable every night. The bag puffs up nicely, and I appreciate the anti-snag zipper that makes it easier to get in and out of the bag. And the water repellent shell and Nikwax Hydrophobic Down provide good protection from moisture.
Parsec 0 Features
Shell: 20-denier, 100% recycled fabric with a durable water repellent coating. Other bags in the Parsec’s weight and temperature range have less durable 10 or 15 denier shells.
Water Resistance: Water that I sprayed on the outside of the Parsec beaded up on the shell, and the bag was dry less than 30 minutes after brushing off the water.
Insulation: 800 fill Nikwax Hydrophobic Down that Therm-a-Rest says absorbs 90% less water and dries three times faster than untreated down. Therm-a-Rest heat maps the insulation, which puts the bulk of the insulation on the bag’s top and sides.
Box Baffles: The Parsec 0 uses box baffles, which are lightweight material placed between the shell and liner to form a box. The boxes eliminate gaps that could create cold spots.
Draft Collars, Draft Tube: Draft collars snugged tight across the forehead and neck prevent cold air from getting inside the bag, and a robust draft tube runs the length of the side zipper.
Hood: Large enough to fit my inflatable pillow and still be able to pull the hood around my head.
Warmth: The Parsec 0 comfort rating is 14F and the low temperature limit is 0F. I was comfortable at 1F while wearing midweight and lightweight tops.
Warm Feet: The down-lined Toe-asis foot pocket, which is a baffled pocket of insulation, provides extra insulation that keeps feet warm.
SynergyLink Connectors: This is the first time I used straps to attach a sleeping bag to my air pad, and I’m sold. Despite my frequent tossing from side to side during the night, the pad and bag stayed connected. I found that I moved inside the bag, rather than moving the bag with me. The straps stretch to fit various width pads, and can be disconnected.
Outer Pocket: The insulated outer pocket is large enough to hold a phone and headlamp. And because the bag is strapped to my air pad I’m not rolling over onto gear in the pocket as I toss and turn during the night.
Zipper: The anti-snag zipper slides easily, but it is possible to snag it on the zipper draft tube, so I still zip with care. A second zipper pull lets you vent heat at the bottom of the bag.
Fit: The Parsec and other bags in this weight and temperature range cut ounces with a slimmer profile, which also means there’s less empty space for your body to heat. I’m 5 feet, 10 inches, and weigh 160 pounds, and find that the 80-inch length of the regular bag is long enough that my head and feet don’t press against the ends of the bag. The 63-inch shoulder girth is good for me, but if you’re about my height and much heavier, you might consider a long bag with a wider 66-inch girth. Even with the Parsec’s slim fit I had enough room inside to store my hiking clothes.
Quilt and Blanket Loops: If you’re worried about staying warm when the thermometer hovers near 0F, a quilt can be attached using the loops. I stayed warm to 1F without using this option.
Stuff Sacks: The storage stuff sack is large enough to hold the Parsec without compressing it, and the bag has two hang loops if you prefer to store it that way. The compression sack helps get the Parsec down to a smaller size for my backpack.
Warranty: Therm-a-Rest will repair or replace gear found to be defective within the first two years of purchase. Sleeping bags are covered under the Better Sleep Guarantee, which means that if you are not completely satisfied with your bag, return it within three months with the original receipt of purchase for a full refund. No questions asked.
Sustainability: The shell and liner are made from 100% recycled fabrics.
Parsec 0 Pros
Weight: 2 pounds, 6 ounces for a regular length. It’s hard to find another 800-fill bag at this weight.
Anti-Snag Zipper: I like that I’m not struggling with a zipper that continually catches fabric.
Sleeping Pad Straps: I’m hooked on the straps that connect the sleeping bag to the pad, ending my sometimes nightlong struggles to stay on the pad.
Toe Box: Extra insulation that keeps my feet warm.
Parsec 0 Cons
None That I Found: The Parsec impressed me in every category: weight, warmth, and comfort. I couldn’t find any negatives.
Overall Value
Yes, the Parsec 0 price ranges from $529.95 for a small to $619.95 for a long. And that’s a lot of money. But this isn’t a stripped down bag, and there are several features that make the Parsec stand out: the anti-snag zipper; the 800-fill down and box baffles; the extra toe box insulation; and the straps holding the bag to the pad. This is a bag I expect to take on winter trips for years to come.
Similar 0F Sleeping Bags
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This product was donated for purpose of review.
