Apple Watch Series 9 45mm case
size Control: Digital Crown with
haptic feedback Side button Double
tap gesture On-Device Siri Display:
Always-On Retina LTPO OLED display
Edge-to-edge display lon-X front glass
(Aluminum cases) Sapphire front
crystal (Stainless steel cases) Up to
2000 nits maximum brightness 1 nit
minimum brightness Chip: S9 SiP with
64-bit dual-core processor
4-core Apple Neural Engine 64GB
capacity Sensors: Electrical heart
sensor and ECG app1 Third-generation
optical heart sensor High and low heart
rate notifications1 Irregular rhythm
notifications2
Sleep stages Temperature sensing3
Compass with Waypoints and
Backtrack Always-on altimeter
International emergency calling5
Crash Detection4 Fall Detection4
Splash, Water and Dust: Water
resistance 50m (swim proof)6