Snow chains
From Wikipedia, the free encyclopedia
Snow chains, or tire chains, are devices which are affixed to the wheels of vehicles to provide superior traction when driving through snow and ice. Snow chains are usually attached to the drive wheels of a vehicle (e.g. the front wheels on a front-wheel drive car), though all four wheels may be chained to provide extra stability. Some owner's manuals for AWD cars specify that two specific wheels can be chained, leaving the other two unchained if necessary.
In snowy conditions, transportation authorities often require snow chains to be fitted on vehicles that lack four-wheel drive and proper tires. These requirements are usually enforced by checkpoints, before which eligible drivers must have snow-chains fitted on their cars. Uproad from such checkpoints, chains can often be fitted professionally for a fee.