Come and see our amazing products. Metal USB both can be used as USB and handring, more kids yougster adults like it, suitable for bussiness gifts and promotion activities. Can do custom color and personal logo. The product support OS: Win98 / XP / Vista / Mac OS9.X / Mac OS Linux 2.4. Maximum reading speed is about 10M/s, and writing speed is about 7MB/s. 521M, 1G, 2G, 4G, 8G, 16G, 32G, 64G can supply. Pls confirm with us about the packing info, stock status and exact production time before placing your orders.