Ford is to fit out its brand new Mondeo next year with an inflatable rear seatbelt.
Effectively, it is an airbag and a conventional seatbelt.
The seatbelt is designed to reduce head, neck and chest injuries for back-seat passengers.
Among the main aims is to provide better protection for children and older passengers.
If there is a crash, the belt expands so that the stress points are dispersed across more of your body (five times greater than that achieved by a conventional seatbelt).
Under normal conditions, they operate like conventional seatbelts. Ford says they are safe -- and compatible with infant and children safety, car and booster seats.
According to research carried out by Ford, more than 90pc of participants in tests found the belts to be similar to or more comfortable than conventional ones because they felt "padded and softer".
The technology, not currently available in Europe according to Ford, was first offered in the US on the 2011 Explorer.
And now for the technicalities. The new seatbelt is activated when crash sensors detect a crash. Compressed gas is forced out of a cylinder through the buckle and into the belt.
It all takes less than 40 milliseconds.