https://www.gamespot.com/articles/nintendo-switch-ac-adapter-on-sale-now-on-amazon/1100-6457768/

Whether you need a replacement for your Nintendo Switch's AC adapter or just want to pick up a second one to keep in a different location, Amazon has a good deal on them now. For a limited time, you can buy a official Switch AC adapter for $24.97, 17% off its normal price of $30.

As Switch players will know, this AC adapter lets you charge the system in portable mode (even while playing) and also powers the dock from any 120-volt outlet. While you're at it, you might want to pick up a Nintendo Switch Pro Controller, which is also on sale on Amazon, for $59 (normal price $70).