Just charge it up and use as a keychain! When your Apple watch is low on battery, simply place it on top of this keychain to charge.

Compact and Convenient Power Bank Keychain for Apple Watch – Mini Wireless Charger

• Efficient Input and Output Parameters: Supports 5.0V-1A input and 5.0V-0.4A output, ensuring efficient charging for your Apple Watch.
  
  
• High Conversion Efficiency: Boasts a conversion efficiency greater than 80%, providing effective power use.
  
  
• Optimal Charging Distance: Designed for a charging distance of ≤ 8mm, offering convenience and ease of use.
  
  
• Compact Size: Measuring 110 x 41 x 14 mm, this charger is incredibly portable.
  
  
• Lightweight Design: Weighing just 53g, it's easy to carry around.