4 Left Side Slots
On the left side of the Apple Watch Series 4, you’ll notice two horizontal slots. These are the speakers of the device.
Apple has redesigned some of the physical elements of its new wearable, and that includes making the speakers on the Apple Watch Series 4 larger — and louder.
While you’ll still need Bluetooth headphones for music and podcasts, the new speakers will allow for a better experience when it comes to notifications, Siri, and phone calls.