Single wheel packs to allow mixing of colors. Order two packs for complete reflective stripes on both sides of two wheels. Fiks:Reflective Wheel Stripes increase visibility for bicycles to keep their riders safe. They are designed specifically to fit modern bicycle wheels by easily sticking onto the non-braking surface of the rim. The special glass bead embedded film reflects light from the headlights of a car back towards the car and the driver to keep you seen and semi-permanent adhesive makes for durable installation that removes cleanly when it's time for change. What size? Choosing the width for your Reflective Rim Stripes comes down to the type of rims on your bike. The rim is the metal ring in which the tire fits to. Several sizes are available to fit almost every modern wheel on the market. 7mm - Our most common size. These are designed to fit on the section of the rim between the braking surface and the spokes/ 14mm - Over twice as much reflective surface area. These are designed to fit aero-style/deep-v rims in the area between the spokes and the braking surface. 10mm - Specially designed for bicycles with disk brakes, drum brakes, roller brakes, a coaster brakes, or brakeless track bikes. These are designed to be installed on the outermost section of the rim next to the tire (where the braking surface would normally be). If your bike is equipped with rim brakes and the rims do not have at least 7mm or 1/4 in. of space between the braking surface and the spokes, Fiks:Reflective Rim Stripes cannot be used– never apply Fiks:Reflective Rim Stripes to the braking surface of a wheel. Info on wheel sizes The most common bicycle wheel sizes in the US are 28in, 29in, and 700c, which are are the same diameter. Note: The referenced sizes of bicycle wheels are designations and not the actual diameters. The actual size of the tires on your bike can be found at the ISO size marking on the tire. The ISO (International Organization for Standardization) measure