Polartec Alpha Direct mummy shaped overbag. Layer on top of any down quilt for cold weather draft control
The Alfabatik Zippered Mummy synthetic insulated bag is designed specifically as a draft stopping cold season companion for quilts and hood-less mummy bags. Too snug for big winter mummy bags - see instead the OG Alfabatik
The mummy shaped design with a close fitting hood just large enough to fit some UL pillow types minimizes drafts from the neck and bottom opening of quilts
It also provides a temperature boost of approximately 5-8 degrees while keeping most dew and mist from penetrating the to the inner quilt
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 and covered with 40 CFM ripstop nylon on top and a near zero CFM bottom material
Advantage of the Alfabatik Mummy overbag over a typical single layer DWR 'bivy': Alpha Direct insulation control moisture and condensation from touching skin and quilt surfaces. Breathing inside the bag is less of a clammy affair. Shaped and tailored fit limits cold air traps and effectively controls typical quilt drafts from movement and wind. Sleeping pad do not go inside
General advantages to using Alpha over the more traditional Climashield Apex insulator:
- 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?
Our sizing options can be configured to ensure an adequate fit with minimum down loft compression.
Typical total weight from 12 oz and up.