195 - Width 45 - % of the width 15 - Rim Stretch began with those running extremely wide rims who couldn't legally run the size tyre suited to it, by stretching, you keep the tread pattern within the wheelarch. In theory it keeps Plod from complaining A lot of people stretch even if they don't have protruding rims though, whether it be to stop tyre rub or just so the car can be as low as poss.