A good survival kit should be designed and put together with its true objective in mind. Different situations and activities can create different emergency scenarios, so it is always best to be prepared for the worst. This way, you are best placed to deal with the problems you are encountering. If you have to deal with savage winter conditions, you need to make sure that your survival kit is appropriate, because it really could mean the difference between living another a day - or not. Winter survival is crucially dependent upon one thing - keeping your body temperature to roughly 98.6 degrees F. You need to be able to limit heat loss from your body but avoid sweating - moisture will ultimately make you colder, and ultimately lead to hyperthermia, so the rule is stay a little on the cool side. This is better than being too warm by wearing layers of clothing, rather than just one heavy item. This will let you adjust your clothing so you can keep to the right temperature. It is important then to have clothing items, preferably thermal garments, in your survival kit so wet ones can be exchanged. Your winter survival kit should include tools and materials necessary to make a shelter.
There are multi-tool pieces that utilize knives, pliers and other devices all in the one tool, meaning you do not have to waste valuable space carrying separate accessories. Although necessary, shelter will bring about its own set of dangers in the winter - you will not be moving so your body temperature will drop, and you could have the additional peril of being wet through melted snow, or through falling into icy water. A sleeping bag that is designed for these extreme temperatures is important for your survival kit, and ideally a strong tent that can be erected quickly and easily. Fifty gallon drum bags can be useful as a waterproof barrier, but care needs to be taken that you don't use them as a way of keeping your body temperature up - they won't breathe so you will sweat and become wet - and colder. The ideal winter shelter will enable you to heat the space around your body, so fire making tools and equipment are a vital part of your survival kit. Matches need to be kept dry, so they will need a waterproof container, but you should also take other fire-lighting tools such as a firesteel, a magnesium fire starter and a liquid fuel lighter. Cotton wool soaked in petroleum jelly ignites quickly so you can have a fire even if your wood is on the damp side.
Put rocks into your fire so you can use them to heat your shelter space when they get hot, and don't forget to include an eight hour candle in your survival kit, so you have the added warmth and light from this too. Ordinarily, food supplies are not as important as other issues when it comes to survival because we can survive for quite a while without it, but winter conditions alter this. Include in your survival kit, high calorie foodstuffs that are nutritious and high quality. Rather than eating lots irregularly, it is better to graze, and to eat little and often to keep body temperatures consistent. The best foods to pack are those that are high in fats and protein, with some sugars for energy. Water is essential for survival, but never try to eat snow or ice - it will take too long to melt in your mouth and the energy it takes will make you dangerously cold. Boiling it over your fire will melt the snow and purify it at the same time. If you have to travel in arctic conditions, it is essential that you have a winter survival kit at the ready because you never know the moment you may become stranded - better safe than sorry may be a cliché, but you'll be glad that you were prepared.