Tyre in size 325/30 R21 is installed in cars of a sports character. The first number is a designation of tyre's tread width (325 millimetres.) The next number is a designation of tyre's profile height. This parameter is expressed in percentage (tyre's profile height is 30% out of 325 millimetres of the tyre's tread width). The capital "R" denotes the radial construction of the tyre. The last number (21) is the diameter of the wheel's rim in inches on which the tyre in size 325/30 R21 can be installed. See our offer of tyres in size 325/30 R21 on our website.