Right and left exts are easily identifiable with unique L and R markings. Use this set with any 9/16 inch threaded pedals to extend the pedal position outward by 17mm (0.71 inch). It prevents knee strain and rubbing against the rear tire/frame. Made of high-quality steel and titanium material, the pedal spacers are anti-rust and durable. The length of the spacers is 3.2cm, width is 1.8cm, height is 1.8cm. They are suitable for bikes and bicycles. Item Name: Pedal Spacers Material: Steel, Titanium Size Details: 3.2cm x 1.8cm x 1.8cm / 1.26 x 0.71 x 0.71 (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension differences due to manual measurement. Package Includes: 2 x Pedal Spacers (Left + Right)