Beautiful Eagle in Flight Spare tire Covers Potable Universal Wheel Covers Powerful Sun-Proof Waterproof Tire Cover for SUV Trai Product Information Material: Polyester Size: 14 Inch, 15 Inch, 16 Inch, 17 Inch Package: 1 X Spare Tire Cover Cover Size Guide Tire Sizes Are Listed On Below Detailed Description, Please Measure Before Purchasing. Cover Size 14" Fits For Tire Diameter 60-69cm/23-27in Cover Size 15" Fits For Tire Diameter 70-75cm/27-29in Cover Size 16" Fits For Tire Diameter 76-79cm/29-31in Cover Size 17" Fits For Tire Diameter 80-83cm/31-33in Spare Tire Cover Diameter Calculation Guide Step 1: Find Your Tire Parameter. It's Written On Your Tire Side Step 2: Calculate Your Tire Diameter If Your Tire Is Written With P225/65r17, A=225 B=65 C=17. Tire Diameter=A*B/500+C*2.54 =225*65/500+17*2.54 =72.43cm According To The Sizing Guide, 14" Spare Tire Cover Is The Size That Fits Your Spare Tire Note: Please Allow 1~2 Cm Deviation Because Of Hand-Cutting And Sewing.