Chances are your car is fitted with either radial ply tyres or crossply tyres. Radial tyres have the word “Radial” on their sidewalls. Otherwise the letter “R” will appear in their size markings,. Eg. 175/70R13 82H.

Structurally, you can differentiate a radial tyre from a crossply tyre by (1) the position of its plies and (2) the presence of breakers.

(1) Plies in a radial tyre lie at 90 degrees to the tread centre line
Plies are the layers of rubber-coated textile cords in a tyre. Together with beads, they form the tyre’s air container, or its casing.

In a radial tyre, the plies run parallel to one another, and lie at 90 degrees to the tyre’s tread centre line. In a crossply tyre, the plies cross each other and run at an angle of about 38 degrees to its tread centre line.

(2) Radial Tyres have breakers
Unlike crossply tyresm radial tyres have breakers. The breakers (or the belt) is made of layers of rubber- coated textile or steel cords (hence the terms “textile radial” and “steel radial”). It is found between the tread and the plies (or casing). The breaker stiffens and supports the tread.