Does the Apple Watch Ultra 2 only support 2.4GHz Wi-Fi?

See the 'Connectivity' section in:

Apple Watch Ultra - Technical Specifications

Wi-Fi

• 802.11b/g/n 2.4GHz and 5GHz

Technical specs for the Ultra 2 have not been published yet. Starting with series 6 both 2.4 and 5GHz bands are supported by Apple watches so I would assume the new series 9 are at least the same.

Connect your Apple Watch to Wi-Fi - Apple Support

It supports Wi-Fi 4, which uses both 2.4Ghz and 5Ghz. And since the previous model supported 5Ghz, there's no reason to think the Ultra 2 won't too.

Apple Watch Ultra - Technical Specifications

Series 6 and up has supported 2.4GHz and 5GHz so there is no reason to assume that the new series would be any different. Apple doesn’t typically go “backwards” when they make new technology. That being said, the amount of data that the watch is going to use for what it does, I can’t imagine that it wouldn’t do just fine even if it was just 2.4GHz, the watch doesn’t need to do anything overly demanding on WiFi. In fact, when connected to the paired phone, it will use the Bluetooth the phone provides.

nzjo01 wrote:

Thanks, I'm confused with an 802.11n standard. Disappointed could not support AX or even AC.

Disappointed? Then don't buy it. What, pray tell, would a watch need WiFi 6 for? Just because.?