Compatible With Apple Watch® And Large Samsung Smart Watches. Removable Insert Ring. Adheres Magnetically To The Back Of Your Smart Watch. Dual USB-A Type-C Outputs. Features A USB-A Or Type-C Input (Cord Built-In). Cord Doubles As Carrying Loop. Requires Your Watch Charger To Charge Your Device. Apple is a trademark of Apple Inc., registered in the U.S. and other countries. Samsung is a trademark of Samsung Group, registered in the U.S. and other countries  .