The product is the Fitbit Flex Wireless Activity Sleep Wristband in Black, designed by Fitbit for iOS operating systems. This activity tracker comes in two sizes, small and large, making it suitable for a variety of users. It is specifically geared towards individuals engaged in running and jogging activities, offering features such as tracking sleep patterns and monitoring daily physical activity levels. The wristband design ensures it is convenient to wear throughout the day for continuous monitoring of fitness progress.
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