Merganser Overbag


This is a made-to-order item. Not in stock. See the home page for the made-to-order lead time.

While we call these “overbags”, technically they are overquilts with a closed footbox and an open upper 2/3rds with a snap closure at the top. The top drawcord can attach to the top drawcord of other Timmermade systems.

Comes in 58″ wide x 79″ long unless specified otherwise. There is a top shockcord and a footbox drawcord. There is a mitten hook at the shock cord exit that can be used to connect to the shock cord exit of another Timmermade system so the two systems stay together. It is possible that it could be used to connect to other systems with a center draw cord or similar attachment point in the center.

Temperature rating is variable, but this overbag will typically add around 20f degrees of insulation to a system.

Measure the outer dimensions of the system the overbag will go over with a soft tape measure. Stuff pillows or similar inside to mimic your body. Do not compress any loft when measuring. Hold tape loosely. Keep in mind the overbag has a drawcord footbox and the total length includes the part that will be cinched up. When measuring the length of the inner system, don’t just measure the horizontal length. Start from the center of the footbox, up, over, and along its length.


Titanium Grey
Moroccan Blue
Dark Olive
Brick Red
Coyote Brown
Charcoal Grey
Deep Purple
Forest Green
Moss Green
If you want to custom fine tune your fit, write in the dimensions you would like here in this format Width x Length. You can take the loose outside measurement of the footbox area of your down system and enter that as the width. Take the loose outside measurement of the length and enter this as the Length. Do not compress your down when taking these measurements. Do not exceed 58" in width or 90" Length. Questions should not be entered here.
Questions should not be entered here.
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The Merganser is a synthetic overbag that can go over a down sleeping bag. Using a synthetic overbag is sometimes a necessary way to keep your down dry in really cold, or really wet environments. In really cold environments the moisture that your body puts out in the night will travel through your sleep system and condense wherever the dew point is, which is typically inside of your down loft somewhere. Adding a Merganser Overbag to the outside pushes that dew point out of the down and into the Climashield Apex batting. From here you can remove the moisture from your down and pack it away dry. The moist Merganser can either be dried during the day, or left moist and packed separately. If the moist Merganser is reinstalled over the down bag the next night your body temperature will continue to push the dew point into the Climashield and the down bag will continue to stay dry. The Merganser will continue to accumulate moisture and will need to be dealt with at some point, but Climashield APEX is remarkably good at dealing with moisture. It does not lose loft and dries very fast.

In really moist environments above freezing, the moisture is likely to come from the outside. A Merganser Overbag is not waterproof, but it can catch light moisture that comes in the form of condensation or contact with wet tent/tarp walls or whatever. This moisture will soak into the Merganser and need to be dealt with at some point, but it creates a barrier between the moisture and your down system.

It also doubles as an insulated poncho. This can allow you to either leave a jacket at home, or at least bring lighter insulating layers. This can often fit over a small backpack too, keeping things somewhat warm back there.

Weight 0.45 kg
Temperature Rating

Adds approximately 20 degrees of insulation (50f stand alone, 2.5oz/yd Climashield Apex), Adds approximately 30 degrees of insulation (40f stand alone, 3.6oz/yd Climashiled Apex)


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