You can easily snowmobile beyond immediate help, so basic repair and survival kits, expandable for longer tours are essential.
The Repair Kit should contain: spare belt spare spark plugs manufacturer's tool kit extra wrenches nuts & bolts sized for your sled tow rope pry bar duct tape wire extra ignition key work gloves
An Emergency Kit should contain: First aid kit sun block sharp knife saw axe map compass mirror waterproof matches or lighter flashlight whistle aluminized blanket high energy snacks extra clothing/socks/mitts