OMM use PrimaLoft® synthetic insulation as it is widely regarded as the best quality available; with insulating properties very close to that of down plus largely manufactured from post-consumer recycled product (PCR). Usually manufactured in a roll or sheet of ‘wadding’, think loft insulation but a lot nicer! From PrimaLoft® we mainly use their Gold Eco with Cross – Core Technology, their highest rated and most sustainable option plus the latest ACTIVE fabric in the Core Ranges, built from a synthetic plume woven through a knitted mesh, CORE offers the warmth of a fleece but with less than half the weight.

Just like owning a top end sports car, a piece of performance Insulation is only as good as how well you care for it. In the same way a sports car still needs oil changes and screen wash, you need to regularly maintain your OMM Clothing to keep it performing at its best. It is important to follow the Product Care Instructions and use the correct wash and/or proofer product as these can affect your clothing’s performance. The benefit of using a synthetic insulation is it is much more resilient when washing plus dries a lot quicker.

That depends how cold you expect to get or perhaps you know you always run a little hot and so don’t need so much. The amount of insulation a product has, generally the warmer it will be. The amount of insulation in synthetically insulated products is quoted as per square metre. When using PrimaLoft® Gold Eco, the lowest value we use is 40gsm, up to 233gsm in our warmest Mountain Raid Sleeping Bag. We also use PrimaLoft® Active which is a much more breathable option as iti does not require the layers of fabric either side of it to stabilise the insulation. Though not as warm aas traditional options, the breathability and next to skin comfort makes it a great option. 

 Most OMM Clothing tends towards the “fitted” end of things. Designed for performance use, the fabrics often work best when dead air is reduced whilst also reducing drag and bulk when moving quickly. We use three different fits in our clothing ranges; Contact Fit, Fitted & Regular Fit. Most of our Insulation uses our Regular Fit, with a little more room and a squarer cut. You’ll find a link to the Fit Guide on each product page. You also find a link to our Size Guide, a more in depth table that shows measurement ranges for each size. Insulation should fit comfortably over a First & Mid Layer and are designed to work well with our Outer Layers. 

 A Sleep System normally just refers to a usually just a standard insulated sleeping bag but there are some other innovative ideas out there such as our own Rotor Sleep System that uses insulated trousers (that unzip to form a half sleeping bag) that then clip into our insulated jackets and the Foot Pod to complete it. So whilst not technically a sleeping *bag* it is an insulated sleep system!

 Well…that’s a good question. Whilst we do use the EN tests for the bags, we do not believe these are the best measure of a bag’s performance. Instead we use Tog ratings for both dry & wet performance (very relevant when using them in the UK!). You can find a comparison table for our sleep system on each product page. For more information on Togs, check out the OMM Glossary. We do not assign a temperature rating to our bags as we believe the figures gained in a laboratory are not necessarily representative. Each person will have a different experience, depending on their size, what they have eaten, their metabolism, what sleeping mat they use and what they wear in the bag. Temperatures quoted from lab testing also do not take into account compression of the underside insulation when you are in the bag, which has a big impact on the true value.

Our Sleeping Bags are primarily designed as a race-weight option for our event held in the UK every October. This means competitors can experience anywhere from -5C (as they did in 2018) to plus 10C and often in wet conditions.

The emphasis here is race-weight, that is to say, users are willing to put up with a certain amount of discomfort for the space and weight saving.  

 Yes! And please do. Just like owning a top end sports car, a performance Sleep System is only as good as how well you care for it. In the same way a sports car still needs oil changes and screen wash, you need to regularly maintain your OMM Sleeping Bag to keep it performing at its best. It is important to follow the Product Care Instructions and use the correct wash  product as these can affect your Bag’s performance. The benefit of using a synthetic insulation is it is much more resilient when washing plus dries a lot quicker. 

 The Tog is a measure of thermal insulance of a unit area, also known as thermal resistance. It is commonly used in the textile industry and often seen quoted for duvets and carpet underlay.
Developed at The Shirley Institute in Manchester, as an alternative to the SI unit of m2K/W.
Basic unit of Tog (insulation coefficient) is the RSI, (1m2⋅K/W). 1 tog = 0.1 RSI: Thermal resistance in togs is equal to 10x the temperature difference (in °C) between 2 surfaces of a material when the flow of heat is equal to one watt per m2. Tog is measured from the difference in temperature between a heated metal plate beneath a fabric and the air temperature above the fabric. This is a much more objective measure than Comfort Ratings, as commonly used for sleeping bags and can be applied to a wider variety of sleep systems. It is also possible to provide a Wet & Dry Tog value, useful when describing use in typical UK conditions.

OMM use PrimaLoft® synthetic insulation as it is widely regarded as the best quality available; with insulating properties very close to that of down plus largely manufactured from post-consumer recycled product (PCR). Usually manufactured in a roll or sheet of ‘wadding’, think loft insulation but a lot nicer! From PrimaLoft® we mainly use their Gold Eco with Cross – Core Technology, their highest rated and most sustainable option plus the latest ACTIVE fabric in the Core Ranges, built from a synthetic plume woven through a knitted mesh, CORE offers the warmth of a fleece but with less than half the weight.