Apple Watch Series 8 GPS + Cellular, 45 mm, Aluminium Case (PRODUCT)RED with Sport Band (PRODUCT)RED (fits 140-220 mm wrists) Your essential companion for a healthy life. Apple Watch Series 8 gives you 18 hours of all-day battery life and advanced health and safety features including fall detection, an ECG app. Additional features include temperature sensing, retrospective ovulation estimates, crash detection for severe car accidents, and international roaming. Crash Detection leverages a combination of an advanced sensor-fusion algorithm, an improved accelerometer and a gyroscope to detect if the user is in a car crash to get help efficiently. If they are unresponsive after a 10-second countdown, Apple Watch will dial emergency services and provide dispatchers with their location. Please note: Find more straps, charging options and headsets under Accessories.