This is a Timex M593 heart rate monitor strap that provides accurate measurements of your heart rate while you cycle. The strap is designed to be comfortable and easy to use, with a sleek black color that looks great on any bicycle. This heart rate monitor is perfect for cycling enthusiasts who want to track their performance and improve their fitness. It is compatible with a variety of Timex models and is ideal for use during any sporting activity. Whether you're a casual rider or a professional athlete, the Timex M593 strap is an essential accessory for your cycling gear.