YIXUAN Universal Treadmill Safety Key Treadmill Running Magnet Security Lock Description Size:Large outer ring diameter 2.8 cm,inner ring diameter 1.8cm,Cord length 1m Packadge Include:2pcs * Treadmill Safety Key Note The size may have an error of 1-2cm. If you want to have different color, you can leave a note when you placed the order Due to different personal measurement methods, there will be an error of 2-4 cm, please understand Thanks for your support About Shipping: All items will be shipped within 3 business days after the payment is received. Most times you will receive them within 8-12 days then. The specific delivery time is depend on circumstances.Any questions, please feel free to contact us During the shopping process, if you have any questions, please feel free to consult us, we will reply you within 24 hours, wish you a happy shopping Thanks for your cooperation and we'll make you feel satisfied.