MPI Outdoors



Technical Information

Product Characteristics

  • The excellent protection against the elements, which the EXTREME Pro-Tech Bag or Vest offers, is due to a combination of design and scientific factors:
  • The thickness and corrugation of the EXTREME Pro-Tech walls create a layer of still air that provides an excellent insulation medium. The metallized surface of the material reflects radiated heat back to the body, and minimizes the emission of radiated heat through the outside of the bag.
  • The elastic strung inner membrane web causes the EXTREME Pro-Tech to hug the body, increasing its overall insulating ability, and reducing any air convection in the space between the bag and its occupant.
  • The EXTREME Pro-Tech is completely windproof, this aids in minimizing any body heat losses due to the effects of wind chill.
  • The EXTREME Pro-Tech Bag or Vest is completely waterproof, and will continue to function perfectly even if completely wet both on the inside and outside.
  • The adjustable draw-cord arrangement around the opening helps to minimize body heat loss through the top opening of the bag.
  • The EXTREME Pro-Tech Bag or Vest is surprisingly tough and durable. The principal construction material (metallized polypropylene) is a strong, lightweight and extremely wear-resistant plastic polymer.
  • The EXTREME Pro-Tech Bag or Vest has a unique patented design that helps ensure that the material is virtually always held in a state of compression, so that tears do not tend to elongate beyond the seams. Any tears that might develop are usually stopped when they intersect with one of the many welded seams in the bag's construction.

Thermal Performance

  • Samples of the material have been tested in laboratory equipment designed to measure the thermal resistance (insulating ability) of textile materials.
  • Table 1 shows the performance of the Pro Tech material compared with that of other well-known sample products. Performance is measured in "Togs", a unit of thermal resistance commonly used in the textile industry.
    • 1 Tog = 0.1 m2K/W (i.e. one Tog is a tenth of a square meter degree Celsius per Watt).

Table 1:
Thermal performance of samples in laboratory tests

Material Tested Thermal resistance (Togs)
EXTREME Pro-Tech Bag 9
Polyethylene survival bag 2
The Original Space™ Brand Emergency Blanket 5
Heavy full size Down Mummy style 6 season sleeping bag (w/outside coated shell) 12
  • The results in Table 1 show that the EXTREME Pro-Tech Bag offers a very high ratio degree of warmth for its weight. This is enough to make a very significant difference to a person's chances of survival in an emergency situation, and easily adequate for lightweight back packing and similar use.
  • All products were tested under laboratory conditions using a man shaped dummy filled with hot water. By measuring the rate at which the dummy cooled it was possible to derive and calculate the thermal efficiency of the sample different bags.
  • The process was repeated on a number of different Pro-Tech bags with varying degrees of previous field and lab use.

Extreme Pro-Tech Bag

Table 2:
Thermal performance of laboratory tests

  Mass/kg Thermal efficiency¹ Warmth to weight ratio
EXTREME Pro-Tech Bag 0.33 1 1
Polythene "survival" bag 0.3 0.16 0.17
Space® Brand Emergency Blanket 0.05 0.46 3.29
3 season synthetic bag 1.95 1.21 0.2
6 season down bag 2.18 2.04 0.3
Wool blanket 0.85 0.28 0.11

¹The thermal efficiency was measured with the bag resting on an insulating mat.

Several important points can be deduced from the test results shown in Table 2:

  • The EXTREME Pro-Tech Bag has shown itself to be equivalent in providing the same degree of body warmth as a three-season sleeping bag.
  • The performances of the EXTREME Pro-Tech Bag or Vest are not affected by previous or multiple use. Bags and Vests were opened and used repeatedly before testing to insure re-use potential.
  • Based on the time proven and life-saving thermal reflective principles of the SPACE™ Brand EMERGENCY BLANKET, the additional insulation medium (trapped air) helps to greatly enhance the overall personal insulation and protection performance of the EXTREME Pro-Tech products.
  • The warmth to weight ratio of the EXTREME Pro-Tech Bag is three times that of a quality heavy 6 seasons down sleeping bag.
  • The warmth to weight ratio is many times that of a wool blanket, a fact with significant outdoor safety implications, because a wool blanket will attract and hold moisture making it less effective, damp and cold.

Extreme warmth for weight graph


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