Features: Unit size: 2.28" x 0.71" x 0.39" (58mm x 18mm x 10mm) (Fold) Weight: about 10g/item Capacity: 4GB Color: Blue Specifications: Chip: Grade A, original brand Interface Type: USB 2.0. Writing speed: 3mb/s-6mb/s Reading speed: 5mb/s-10mb/s Compatibility: Desktop, Laptop, Macintosh, Tablet, Speakers all with USB port Operating System: Windows 7/Vista/XP/2000/ME/NT, Linux and Mac OS Operating Temperatures: 32° F to 140° F (0 °C to 60 °C) Storage Temperatures: -4° F to 185°F (-20°C to 85°C) Note: All product outward appearance, the color take the material object as the picture only supply the reference. Package Includes: 50 x 4G USB Flash Drives Tips: Some of the listed capacity on a Flash storage device is used for formatting and other functions and thus is not available for data storage. Therefore, the exact available capacity for data storage is less than what is listed on the products. Service: Thank you for choosing RAOYI products. If you are not happy with our products, please do not hesitate to contact us. In every customer relationship, RAOYI strives to be a trusted partner and seeks to achieve 100% customer satisfaction.