This product is a carefully designed and produced Vband connector, suitable for vband websites and used by VBand software! Stable performance! Easy to carry! This product is used with the website: supports manual keys and automatic keys! The key interface of this product is a 3.5mm diameter key interface! The key plug must be 3.5mm to use this product. Non-3.5mm key plugs require a simple conversion connector or conversion cable. The vband website used by mobile phones requires to prepare 0TG adapters or OTG connection cables! Computer version: supports automatic identification of manual keys and automatic keys. The computer installs the practice software Lakey, the default manual key, and the key type is modified when using the automatic key. Click the button Manual in the middle of the software page to select the key. Put the cursor in the Cw box to practice. The computer version can also be used on the vband website, but the setting options need to be modified. If you troublesome, you can purchase the vband version separately. The website does not need to modify the settings to practice communication directly. This series of trainers all intelligently identify automatic keys and hand keys. The electric key must first be connected to the electric key and the trainer, and then connected to the computer. No other operations are required. This series of trainers supports , iOS, Android and Hongmeng systems, and are all plug-and-play. Due to different batches, there may be differences in product appearance, color, and printed text, which not affect the use. Specification: Vband Colour:Green Material:PCB Package Contents: 1 x CW Key Trainer Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.