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Polartec Alpha Direct zipper-less, hood-less overbag. Layer on top of any down quilt or mummy bag to boost temperature and manage moisture.

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The Alfabatik zipper-less synthetic insulated bag is a cold season companion to any down quilt or mummy bag needing a temperature boost of approximately 5-8 degrees, and, more crucially, to apply moisture protection and management of one's sleep system during challenging four season conditions.

The simplicity of the Alfabatik full bag design, minus hood, eliminates the drafts and complex strap systems often encumbering the layering of quilt-on-quilt. In extreme cold a quick setup of one's sleep system can be crucial; the over-bag concept facilitates this. 

Having a quick drying synthetic insulated layer towards the outside will aide significantly in moving moisture away from the down filled inner bag/quilt (not included!). 

The approximate 3 oz/yd Polartec Alpha is an ultralight fleece style knit with an open, mesh-like appearance. It is a stand alone product that we cover only on the shell side with fabric. For this we use a 7d nylon ripstop with a 'hot cire" treatment, resulting in a windproof, water resistant performance, with long lasting properties. This low-permeability shell is crucial for heat retention and as a barrier against outside moisture infiltration.

The Alfabatik is a zipperless and hoodless bag with a drawstring controlled top opening and a sealed mummy style foot box.

General advantages to using Alpha over the more traditional Climashield Apex insulator:

- The 7d hot cire shell is like the waterproof bivy we've always wanted but without the dripping wet greenhouse condensation risk

- Very low bulk. Foldable and compact in the pack.

- High resistance to compression damage from repeated stuffing and unstuffing. High loft Apex could be no warmer than Alpha after hard use.

- Can be slept on with limited risk of loft damage.

-Good long term durability compared to Apex.

- With the Alpha exposed to the inside of the bag it is simple to monitor moisture content and long term degradation.

- Like any woven or knitted material the appearance is consistent and even, unlike Apex which varies from wafer thin to full thickness from yard to yard.

- The low bulk makes the Alfabatik an unobtrusive day hike companion for the unexpected, especially if lined with a space blanket type product.


-  Not as warm for the weight as Apex; ie where is the dew point really?

- Expensive, especially when pared with a techy shell like the 7d hot cire

Our sizing options can be configured to ensure an adequate fit with minimum down loft compression.

Typical total weight from 12 oz and up.   

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Polartec Alpha Direct zipper-less, hood-less overbag. Layer on top of any down quilt or mummy bag to boost temperature and manage moisture.

Product Options
Overall Width
Regular - For moderate width quilts
Regular Plus - For wide quilts or mid range mummy bags
Wide - For winter mummy bags
Narrow - For the smallest quilts
Inside Length
64" For extra short quilts/bags
68" For short quilts/bags
72" For medium quilts/bags
76" For long quilts/bags
80" For extra long quilts/bags
Shell Material
Grey 7d Nylon Ripstop Windproof/Water Resistant
Olive 7d Nylon Ripstop Windproof/Water Resistant

Polartec Alpha Direct 4004 - Olive Grey
Your Measurements
Shoe Size 
What are you layering over? Type, temp, brand 
Stuff Sack
Yes, please include a stuff sack
No stuff sack