Please buy according to the size corresponding to your calculations and not directly according to the tire size! How to choose the most suitable size? Step 1: Find Your Tire Parameter. It's written on your tire side Step 2: Calculate Your Tire Diameter According to the Parameters Calculation formula: (A*B*2)+(C*2.54) If your tire is written with P225/65R17, the parameters correspond to A=22.5 B=0.65 C=17. Tire diameter=(22.5*0.65*2)+(17*2.54)=72.43 cm You need to buy the 15 inch size. There are three size size 14 inch fit for: diameter 60~69cm size 15 inch fit for: diameter 70~75cm size 16 inch fit for: diameter 76~79cm