Size can be adult and youth. We can print a logo on the central part of it. Capacity can be 512MB, 1GB, 2GB, 4GB, 8GB, 16GB, 32GB,64GB. Operating Temperature is -32°F to 140°F (0°C to 60°C). Storage Temperature is -4°F to 185°F (-20°C to 85°C). Read speed 18M/S,write speed:3.8M/S (USB2.0). Working voltage is 5V with wrking power 300mA. Guaranteed 2 ear warracustom-rubber-braceletsnty. Operation system Windows 98/ SE /ME /2000 /XP/ 7/ Vista, Linux 2.4.x, Mac Windows 7, etc. The advantage of our product. 1. Make logo according to customer"s design, 2. File preload, files can be non-erasable. 3. Advertisement files Auto-play once USB was plugged into the computer. 4. Website auto pop-up once USB was plugged into the computer. 5. Disk partition. 6. Password protection. silicone-wristbandrubber-message-bracelets are inexpensicustom-rubber-braceletsve and yet highly effective in promoting a cause or a product that many business organizations, groups, and even individuals use it to meet their objectives. These wristbands come in different styles, colors, designs and sizes; and all kinds of variations are available to suit your taste, requirements, and budget. There are many wristbands sizes available in the market. To help you choose the best one, here are some details about their sizes: General size (adult): 8 "(L) x 1/2" (W) x 1/16"(H) or (202MM x 12MM x 2MM) Women"s size (adult): 7.5 "(L) x 1/2" (W) x 1/16"(H) or 190 MM x 12MM x 2MM) General size (children): 7 "(L) x 1/2" (W) x 1/16"(H) or (180MM x 12MM x 2MM) 61/2 "(L) x 1/2" (W) x 1/16"(H) or (165MM x 12MM x 2MM) The maximum screen printed and engraving area for adults is 7.677"X 0.334" The maximum area of screen printing and engraving for children is 7.00"X 0.334" As for width, commonly used are: 1/4 "or 6MM 1/2 "or 12MM 3/5 "or 15MM 3/4 "or 19MM 1 "or 25MM rubber-bracelet-maker-online We are professional rubber bracelet maker with years of experience. Rubber bracelet is not only used as promotional gift, but also as a medical alert tool. Medical alert bracelets is commonly used. It is a high quality rubber bracelets with the ID printed on. We can print bar code, QR code or unique serial number together with some detail of the medical institute. Usually the wristband width need at least 15mm so that the code is clear enough to be scaned. We you scan the code with a phone, the detail of patient name, disease, taboo drugs, status will show up. It is a good help for doctor and patient to know the treatment. All the medical bracelets should made from 100% silicone which is harmless and eco friendly to avoid secondary injury to patients. If the bracelet is embeded with a chip, it will note down the information of exercise, heart beat and sleeping. Then trafer it to the phone app. It contribute to health care.