Backpacking, trekking, hostelling, and adventure travel often don't require the warmth of a sleeping bag. Instead, something thin to keep the chill off, and to protect you from potentially dirty beds, is all you really need. While travel sheets or even a fleece blanket will do in these cases, they are not as flexible or comfortable as a Travel Sack from REI.

So what is a Travel Sack? Essentially, it is a very lightweight sleeping bag, but with some added features that you won't find in most sleeping bags. Here's what makes the REI Travel Sack world class:

• For warmth down to about 50 to 55 degrees or so, the Travel Sack is filled with synthetic fiber. Because the fill is synthetic, it has some insulation value when damp or wet, and it dries quickly if it gets wet.
  
   
• The Travel Sack can hold people up to 6 foot 6 inches (there is only one size), and the shoulder girth is 60 inches. The girth might be a little narrow for burly individuals. Even if you are short, the long length of the Travel Sack should not be an issue as keeping really warm in the sack is generally not the point, as it is conventional sleeping bags. For standard sleeping bags, you don't want a bag that is too long because the extra space can contribute to less warmth.
  
   
• The Travel Sack is lightweight, about 1 pound 9 ounces, and compresses to about the size of a 1 liter bottle. This means you will barely feel its weight, and it will take up very little room in your backpack or luggage.
  
   
• The Travel Sack has a hood that can be drawn around your face if it gets colder than you expected.
  
   
• The Travel Sack also has a small zippered pocket you can use to store your passport, money, watch, etc., close at hand.
  
   
• Now here is really where the Travel Sack shines, and that is in the area of ventilation. In warmer weather, I often find myself too warm rather than too cool. If I get too warm in the Travel Sack, there are several ways I can cool down.
  
   
  • First, I can unzip the long zipper, from the front or back of the sack.
    
     
  • Second, there are two smaller zippers on each side of the Travel Sack that can be used for extra ventilation, or you can even stick your arms out if you like.
    
     
  • Third, the bottom of the Travel Sack has a foot opening that allows additional air to flow through the sack. On colder nights, it can be sealed for extra warmth.
    
     
• The REI Travel Sack can also serve double-duty as a liner bag for your regular sleeping bag if you need some additional warmth. Or, you might want to bring it along on a day hike or climb just in case you find yourself stuck out all night unexpectedly.

Not only is the REI Travel Sack a great product, it is also inexpensive, running $59.00, less when on sale.

Using the REI Travel Sack in the Real World

I am 6 foot 2 inches and 200 pounds, and I find that the Travel Sack fits me very well. There is more than enough room for me to roll around in it. I generally sleep in the sack using a lightweight base layer, or just my underwear if it gets too warm.

The rated low temperature of +55 degrees is somewhat nebulous. In other words, the lowest temp you will be comfortable in with this Travel Sack will depend on how you have the sack ventilated, what you are wearing, the ambient temperature, the humidity, if you are inside a building, a tent, or sleeping in the open air, and so on. In many cases, you should be able to stay warm in temps as low as 45-50 degrees if you are wearing sufficient clothing and aren't exposed to any moving air.

On the high side of the temperature range, you should feel comfortable up to about 70-80 degrees or so. If you get too warm, you can just sleep on top of the sack.

My favorite feature of the bag is the ability to stick my feet out of the bag when I get too warm. For some reason, I have always found this one of the best ways to regulate my sleeping comfort, even when sleeping in bed.

Even with good ventilation, I sometimes still find myself perspiring a little inside the bag. In these cases, I always make sure to let the bag air out before packing it for the day.

Recommendation

If a conventional sleeping bag is too warm, then consider a sleeping sack. With the REI Travel Sack, you can't go wrong.

Product Notes

The REI Travel Sack comes in only one size and one color (medium grey). The MSRP is $59.00. The sack is machine washable and dryable.