We offer otg usb flash drives for smartphone, customized shape/logo/packing. Product advantage 100% full capacity: our products with excellent quality and performance, through full testing and certification using only major brand flash chip material ic capacities: 128, 256, 512mb, 1, 2, 4, 8, 16, 32, 64, 128gb data retention: 10 years more than 1, 000, 000 times data encryption usb interface: usb2.0 (also compatible with usb1.1 and 1.0) usb3.0 (follow customer request to made) logo ways: silkscreen printing, laser engraved logo and more operating system: windows 7, windows xp, vista, windows 2000, linux kernel 2.6.x or late, mac os 10.x or later voltage communication range: 4.5-5.5v with ce, rohs, fcc certificate our mission for customers: provide accurate and timely market information, high-quality products, competitive pricing and value-added services resulting in a "win-win" outcome for all parties.