The Big Agness Hitchens UL is designed for adventures when every ounce is counted, space is anything but abundant, and performance is not to be overlooked.  This bag is constructed with water resistant materials and has well thought out features to enhance your sleeping experience.

The down used has been treated with DownTek for water repellency and is Responsible Down Standard (RDS) certified. DownTek down absorbs 30% less water than untreated down, and dries 60% faster. It retains the same fill power as down, does not add any measurable weight, and can be machine washed with no consequence to the water repellency. The treatment creates surface tension on the surface of the down cluster so that moisture forms into beads and rolls off, as opposed to saturating the material. DownTek is PFOA and PFOS free and are environmentally friendly.  The RDS certification safeguards the well being of geese and ducks, and ensures that the down used is sustainably sourced. All this down is cocooned in between a nylon ripstop shell and liner; and in addition to the DownTek™ water repellency, the shell has been treated with a Durable Water Repellant (DWR) finish.

The bag features vertical baffling (head to toe) which allows air to move the full length of the body. This design is desirable as it spreads warmth throughout the entire bag as opposed to keeping it isolated to one area area; as is the case with horizontal baffeling. Though vertical baffles, or channels, are often avoided in order to manage down-shifting (the displacement of down to either end of the channel), Big Agnes makes use of FlowGates™ as part of the Insotec Flow™ system to circumnavigate the issue. Staggered throughout the Vertical Thermal Channels™ (VTC™) are specialized ‘gates’ which allow air to flow the length of the channel while keeping the insulation in place. Not only does this design eliminate cold spots due to uniform heat distribution, but it requires fewer baffles. Fewer baffles = less material = lighter gear.

Many of the bags from Big Agnes feature the cleverly named Big Agnes System which replaces the insulation normally placed at the bottom (between you and the ground) of the bag with a sleeve for your sleeping mat. The Hitchens is back to the traditional mummy design with insulation around the entire bag. The mummy shape and the VTC™ combine to create a bag that conforms to the body no matter how and where you roll in your sleep. The ergonomically designed foot box provides more loft for extra warmth, and the mummy hood features a draft collar to keep the warmth where you want it.

The half length YKK zipper leaves less opportunity for cold air to enter, or for warm air to leave. It’s lined with a 3D anti-snag zipper tube which basically looks like a draft guard on both sides of the zipper. The ‘one-handed cord-lock’ facilitates easy adjustment to the mummy hood when you need to batten down the hatches, or open up and get some fresh air. The left and right zippers of two different bags can also be zipped together if you want to get cozy with a friend. 

• Draft collar.
• Insulated mummy hood with one-handed cord-lock.
• Body mapped Insotect Flow baffle construction.
• Half length YKK #5 zipper.
• 3-D anti-snag draft tube and zipper garage.
• Rip-stop nylon shell and liner.
• DWR finish on shell.
• DownTek water repellant.
• Mesh storage sack and nylon stuff sack.
• Exterior drying/storage loop.

Very well thought out. 
Much like the incomplete sentence above, this bag does away with anything that’s not essential. They chose excellent materials, and used as little of them as they could in order to create the lightest and warmest bag possible. 

The bag weighs in at 879 grams and has a temperature rating of -8.9°C at the low end. When compared to the Klymit KSB Sleeping Bag which has a weight to warmth ration of 1.4kg/-6.6°C, and the Rab Infinity 300 (Gear of the Year winner in 2016 ) with a ration of 656g/3°C, the Hitchen’s weight/warmth ratio is looking pretty impressive. 

Price seems to be where this bag falls behind. It’s more expensive than both the Rab Infinity 300, priced at $600CA, and the Sea to Summit Spark SPIII (2014 Gear of the Year winner) which will run you $459US. But in this case, the extra money is not unwarranted; the water repellency of both the shell and the down is worth a few extra coins, and the RDS certification means you can feel good about where the down came from.

Warm, light weight, water repellant, and made with sustainably sourced down?! If you have the coin, this bag is worth every penny. 

For summer rated sleeping bag reviews click here and for more 4 season reviews click here.