It is a type of suspension in which, by keeping the body fixed and moving a wheel there is no geometrical variation compared to the other. The two most common types are the quadrilateral suspension and the Mc Pherson.

Letting pressurised air into the tyre by means of the valve.

Pressure of the air inside the tyre (higher than atmospheric pressure); due to the deformability of the tyre, it enables it to withstand the loads on the vehicle, absorbing part of the impact energy caused by the irregularities of the road and to maintain the series of features like handling, stability traction and fatigue resistance of the structures. Incorrect pressures have a negative influence on the general behaviour of the vehicles as well as on the kilometric lifetime of the tyres.

It is the most internal tread layer in contact with the belt or where there is no belt (conventional structure), with the last ply of the carcass.

It is a natural or synthetic rubber ring shaped tube with a valve which has the job of closing the pressurised air in the tyre as impermeably as possible, allowing it to perform the functions for which it was designed.

It is a layer of a special compound which ensures an airtight seal.

The area of a toroidal surface extending from the minimum internal diameter to the diameter where there is the maximum transversal width (chord) is called intrados.

Operation of inverting the tyres on the axles without changing sides, to be performed every 10,000-15,000 km to improve wear and to be able to change them all at the same time.