It is a product user manual of Fitbit Flex on their product website. Last weekend, I got this wristband as a gift and had no idea what it is and how it supposes to work. Fortunately, the user manual explained the multi functions of this product and its technical specs in a very concise way. So I was able to learn this new concept of “lifestyle tracker” and understood how it works in less than one hour. They use bullet points, short paragraphs and illustrative pictures to deliver the most important knowledge that the customer should know about their product.