Why do some trucks have chains hanging?
Chains are fitted underneath the ambulance to ensure the vehicle is always grounded. … By suspending a chain beneath the vehicle, the charged electrons move to the less charged ground below. This effectively protects the vehicle from static electricity.
Regarding this, Who invented on spot chains? The Onspot Automatic Tire Chain System was invented in Sweden in 1977. It was developed and marketed by Onspot AB, a subsidiary to the Swedish VBG Group (public).