Feature: 1. Super fast response, strong anti-interference ability and high cost performance. 2. Ultra-low energy consumption and long transmission distance. 3. For ESP-01 wifi adapter module, the 3.3v voltage stabilizing circuit and the on-board level switching circuit, make the 5V singlechip easy to use with the esp-01 wi-fi module. 4. In addition, the product can be used with for R 3 or compatible board. 5. Made of high quality material, it has strong durability. Specification: Condition: 100% Brand New Item Type: Wireless Adapter Module Material: Metal Color: As Pictures Shown Operating Voltage: 4.5-5.5V (onboard 3.3V LDO Voltage Stabilizer) Operating Current: 0-240mA Interface Logic Voltage: 3.3V / 5V Compatible (on-board Level Conversion Circuit) Package List: 2x Wireless Adapter Module Super fast response, strong anti-interference ability and high cost performance. Ultra-low energy consumption and long transmission distance. For ESP-01 wifi adapter module, the 3.3v voltage stabilizing circuit and the on-board level switching circuit, make the 5V singlechip easy to use with the esp-01 wi-fi module. In addition, the product can be used with for R 3 or compatible board. Made of high quality material, it has strong durability.