The simplistic - less than detailed suggestions that you might get from certaingovernment entities or the fluff safety sites do you a disservice and likely insult your intelligence. Here are some pics and some basic tips.
Mobile Phone Charger - make sure it is for the phone YOU are using and Label it as such.
All current model phones if not activated - can be used for 911-ONLY Calls
Keep old phone programmed with Emergency Numbers and Charged/Spare Charger - Label With an ICE Sticker & 911-ONLY. Store in Sealed Clear Container
Blankets - Synthetic or Wool - NEVER COTTON.
Mylar Rescue Blankets Reflect Heat and Take Up Far Less Space
Best Bet - If You Can Afford Them - Sleeping Bag - Synthetic Fill or Down (Lighter-Smaller)
Flashlights - LED Headlamp would be a smarter choice - one that is powered by LITHIUM Batteries - CR123 Cells Get High Quality Polymer Flashlight (Laser products) that operates on CR123 Cells - they function at lower temperature.
Spare Batteries - Yes - spare Phone Battery as well Place Purchase Date and Self Imposed refresh date on container.
Candle - Carry a 120 Hour 3 Wick Candle as Well for Heat/Cooking and Light Waterproof Matches Sealed in a Container With Strikers or even Better a Survival Butane Lighter - Windproof Model for Fire Starting
Tools: Good Survival Knife from Gerber, Buck, Leatherman Tool - Standard Tool Kit - once again, no junk as it will fail. Duct tape, paracord, screwdrivers/torx/allen/wrench/multisocket tools/fuses/plastic sheeting or tarp to name a few.
Signalling: 30 Minute Fusees, LED Flashers or Marine Strobe Lights - Especially Useful if on the move or you need to start a fire in wet weather. A Survival Mirror wold be helpful but you can use the vanity mirror on your visor.
First Aid Kit - Make it Yourself - the store bought Ones are usually insufficient except for scratches - likely you are off the road and injured. Adventure Medical Kits are available in sporting stores and online - start there. If you take meds you better take a supply with you before you trek off through the mountains like some diabetics did last year....foolish.
Food - Solas Rations (Boat Rations) should be stored on board - they take up less room and are made specifically for this reason and spoil on you. U can get 3 days worth about the size of a laptop. If you are going for a ride of course take some food to eat along the way and to have for an emergency as well. you could store MRE's in the winter months if you have the room.
Food Prep: Get a small mess kit from Gander or Boy Scout Store or an old military surplus canteen and cup to cook anything else you might happen to acquire and be able to melt snow. You might be stuck longer than you think.
Water: Without Water You Die - Simple. store Treated Water on Board Have a Way of Purifying water you secure from melted snow or streams. Learn how to use it beforehand.
Clothing - Synthetics are Best - Thermal Underwear/Socks/Liners/Wool WatchCap/Sythetic Full Hood-Mask/ Mittens-Liners/Spare Underwear / Down Jacket - NO COTTON. Package in Stuff Sack or Backpack - Always carry a pair of season appropriate shoes/boots in a bag with socks inside already.
Sand/Litter - You call on that - consider rock salt mixed with the sand - carry in a durable container - you will get friction if you use it....best of both.
Jumper Cables - When you are rescued you likely will need a jump start - select the largest gauge cables you can find if you have a large battery (6 GA)
ICE Scraper - We would hope you had one of these already either part of the extendable snow brush or along with your snow shovel.
Snow Shovel - Don't rely on junk - it will break - instead get a short wood or plastic handled flat steel shovel (aka "banjo") for about the same price
Fire Starting Kit - Windproof Butane Lighter, Boat Matches, Striker Kit, Solid Fuel Bars, Magnesium Striker, Waterproof Case (like Military Decon Kit or Snap Lid Box)
Compass/Map: Sure your phone had those features but it is broken...and maybe you subscribe to a vehicle safety system...or maybe not. Last resort....map and compass.
Sanitation: You will begin to stink in a few days and you will have to relieve yourself...go outside or stay inside - make preparations for that...Wag Bags, Old Drink Containers and of course - toilet paper.
You can certainly add more gear as you see fit but this is a minimum kit.
Of course make sure your vehicle is up to the task and you have it properly serviced and all your spare tires and parts are functioning or on board.
