Big Agnes Horse Thief SL 35°


fall 2010 regular long
Weight 1 lb 11 oz / 770 g 1 lb 15 oz / 880 g
Fill weight 12 oz / 340 g 14 oz / 400 g
Temperature rating 35 F / 1.7 C
Fill 800 fill down
Shape mummy
Max user height 5 ft 10 in / 180 cm 6 ft 6 in / 200 cm
Shoulder girth 67.5 in / 171 cm 72.5 in / 184 cm
Hip girth 64 in / 160 cm 69 in / 180 cm
Foot girth 43 in / 110 cm 44 in / 110 cm



I originally purchased this bag with the insulated-air…

Rating: rated 4 of 5 stars
Design: Mummy
Fill: 600 fill down
Temperature Rating: 35 degrees Farenheight
Weight: 1.5 lbs
Price Paid: $170

I originally purchased this bag with the insulated-air core pad for the affordable savings in weight. For the money, there's no seeping-pad / bag combo out there that hits my sweet-spot for comfort, warmth, weight and price. The bag and pad together weigh under 3 lbs and I spent around $250. Used to be if you wanted something this light, you'd have to pay a mint for something potentially flaky. So for me, this is a bargain.

I love down bags, and the bag is lightweight and warm--so far down to 45f. I find the quality of the bag excellent too. It feels very sturdy, the material is very comfortable and the workmanship is top-notch. I love the way it mates with the the insulated air core pad, so it's hard to roll off of the mat.

There are always trade-offs, and for me, this combo hits the sweet spot of comfort, warmth, weight and price. For my money, nothing else compares.


I was really disappointed in this bag. I needed a…

Rating: rated 0.5 of 5 stars
Price Paid: $180

I was really disappointed in this bag. I needed a bag to use in temperatures from 30-50. I read all the reviews and narrowed it down to the Horse Thief 35 degree and the Marmot 40 degree bags. I purchased both bags so my wife would also have one.

At 40 deg my wife was cold all night which was surprising since she is a very warm sleeper. I tried the bag also at 40 degrees and was cold all night also.

I really like the bag design and roomy size but had to return it because it was not close to its rating. With the Marmot Atom 40 degree bag I slept comfortable at temperatures down to 33 and 30 degrees which was surprising for a 40 deg bag.


I really like this bag and the integrated Big Agnes…

Rating: rated 4 of 5 stars
Price Paid: $135

I really like this bag and the integrated Big Agnes pad system.  It packs down super light and small and feels roomy enough for me and my big manly shoulders (I'm a tick under 6'0, a tick under 200 lbs., and I have the long version of this bag). 

I don't think I've gotten close to pushing the 35 degree rating, because cold weather camping is for maniacs and insane people, so I'm withholding a star until I can confirm the rating. 

In short, this is my go-to bag until further notice.  I got a crazy good deal online, too (think it was a returned item or a second or something like that).


Not for me this. I spent three nights with the Horse…

Rating: rated 1 of 5 stars
Fill: down
Price Paid: GBP200

Not for me this.

I spent three nights with the Horse Thief and mummy sleep mat combo and didn’t have a good night’s sleep once.

There has been a lot said and written about the Big Agnes system, which in theory seems a winner. However, I found myself cocooned in the bag and any movement caused the whole thing, mat included, to tilt off the deck with me. It felt as if my legs were taped together.

I ended up removing the pad form the sleeve and reverting to a traditional bag on mat set up. It also made a right old racket each time I moved, with the noisy squeaking mat causing much mirth among my pals next door.

Unless you can sleep flat on your back, with your arms by your side without moving for six hours, this isn’t for you. Their claims of it being like your mattress at home are just fanciful marketing spiel.

Thankfully the good people at Big Agnes have been very helpful and accepted the return. I will be reverting to bag and mat. In their defense, I may have been better suited to a non-mummy type bag, but I would still think long and hard about going for this new system.

Make sure you choose a model large enough that enables you to move on your axis without the whole thing moving with you. A shame, because the Big Agnes tent I bought with it is superb.


This is a nice comfortable bag. If you are larger…

Rating: rated 4 of 5 stars
Design: mummy
Fill: 725 down
Temperature Rating: 35 f
Price Paid: $112

This is a nice comfortable bag. If you are larger than 5' 10" and weigh more than 200 lbs. it may be too small for you. It was perfect for temperatures in the 50s so the 35 degree rating may be optimistic. Light and packs small.

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Big Agnes Horse Thief SL 35°


The Big Agnes Horse Thief SL 35° is not available from the stores we monitor. It was last seen March 6, 2015 at

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