Shell structure: engineering plastic shell, beautiful and exquisite, super fall-resistant and wear-resistant 2. Instruction method: LED flash indicates working status 3. Power supply method: direct power supply can be supplied by USB cable 4. Applicable models: Z-3000, Z-6200, Z-6200C, Z-6200D, Z-6200E, Z-6600, Z-6500D, Z-6800 and other drive-free machines 5. Communication method: with computer: USB cable; with machine: standard communication cable/contact connection of the machine (Z-6200C, Z-6200D, Z-6200E only) 6. Security: Data can be saved for 30 years after power loss