Usage Tips:[Premium Materials] For Dolphin pool cleaners, keep your for Dolphin robot working efficiently and it lasts longer. They are perfect for keeping your pool safe and functioning properly. Replacement Pool Cleaner Timing Tracks - Keep your pool cleaner in top condition with this replacement timing track. Improve the Performance of Your Robotic Pool Cleaner - Worn tracks can cause a variety of performance issues with your automatic pool cleaner. It can start with slow movement, lack of traction on the pool floor, and inability to climb walls. Don't wait until your cleaner starts to malfunction. Replace Timing Tracks in Pairs - It's tempting to replace only one track that looks more worn. But is, it 't take long for the other timing track to catch up with the wear of its paired track. Wear isn't always obvious, especially with timing tracks that wear in a steady and clean pattern. But as a rule of thumb, timing tracks that are over 2 years old should be inspected for wear and replaced as needed. Colour:As Shown Material:pp Package Contents: 2 * Underwater robot transmission belt Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.