If you've got yourself a brand new Apple Watch 9 or any other model of the smartwatch, be wary of counterfeit and uncertified chargers – they could affect charging speed and even reduce battery life on your wearable, Apple says.
This is all spelled out in a new Apple support document (via ZDNet), with the company recommending "charging your Apple Watch only with chargers made by Apple or chargers that have completed Apple MFi certification and use the Made for Apple Watch badge".
A couple of images of Apple-made chargers are included for reference, and some of these chargers also have text and regulatory markings on the cable to help you identify them (below). The same page lets you look up the model numbers for these official chargers.
If you're not going with a charger made by Apple, get one that has completed MFi certification – that's 'Made for iPhone/iPad' (and Apple Watch nowadays), and it means Apple has taken a look at the device and given it the thumbs up. These chargers will have a note to this effect on their online listing or packaging, and there's also a public database.
Advice worth heeding
It's something of a surprise that this support document has only just appeared, as you don't want to be entrusting the charging of your Apple Watch to a device that isn't well made for the job. That's part of the reason that the MFi certification process was introduced in the first place.
Besides erratic charging speeds and reduced battery lifespan, Apple also mentions "repeated chimes" as a potential problem – in other words, the watch being given the wrong information about the charging process.
This all applies to any kind of charger for any kind of gadget really. You're always best going for an official option or a recognized and certified third-party solution, rather than the cheapest model showing up online.
In other words, it's worth paying a little bit extra to get something that's safe and reliable. Take a peek at our best Apple Watch charging stands guide to see some of your options, which include official and MFi certified picks.