
With the launch of the iPhone 12 models last year, Apple introduced a $129 MagSafe Duo Charger that's able to charge an iPhone and an Apple Watch at the same time, but it's unfortunately already outdated.

The Apple Watch Series 7 has a new fast charging feature that requires an updated charging puck, and that means the Apple Watch Series 7 does not fast charge when connected to the MagSafe Duo as it uses a standard non-fast charge puck.
Apple confirmed that the MagSafe Duo is not able to fast charge an Apple Watch Series 7 in a support document updated this afternoon.
Apple may have an updated version of the MagSafe Duo that supports Apple Watch fast charging coming in the future, but Apple Watch Series 7 owners who already own the current version will need to settle for standard charging speeds.MagSafe Duo Charger doesn't support fast charging with Apple Watch Series 7. To fast charge your Apple Watch Series 7, use the Apple USB-C Magnetic Fast Charging Cable.
Article Link: Apple's $129 MagSafe Duo Charger Can't Fast Charge Apple Watch Series 7