Compatible With Fitbit Charge 4/ Charge 3 Classic and charge 3 SE(Special Edition). 1 Pack, 2 packs and 3 packs can be available for office, home, car and travel ect. Support charging and data transfer. Compact and Portable design, great for travelers and business users. NOTE:  Please  plug into the USB port onto PC, Laptop, Mac or Notebook. If you connect it to the adapter, the current must not exceed 1A. Clip design and connector makes it more convenient and efficient to to charge your Fitbit activity tracker with ease. Eco-friendly material and High performance and good quality USB charging clip ensure enhanced faster charging speed. Output short circuit protection, safer for your Fitbit Charge 4/ Charge 3 fitness heart rate. 1-Year Warranty. Unconditional refund or replacement for any quality issue