ICE dot crash sensor
DescriptionThe Crash Sensor will mount onto any helmet and when paired with the ICEdot app over low energy bluetooth, the system is able to detect motion, changes in forces and impacts.
Physical & performance 
Dimensions12 x 7 x 7 cm
Display size
Display resolution
Touchscreen
Color display
Weight68 grams
BatteryRechargeable via USB
Battery lifeOperating time up to 20 hours; standby time up to 30 hours.
Water ratingup to 1 meter for 30 minutes
GPS enabledYes
GLONASS
Maps & memory 
Maps and routes
Ability to add maps
Accepts data cards
Sensors 
ANT+ cadence/speed
ANT+ heart rate strap
ANT+ power meter
ANT+ Trainer Control (FE-C)
Bluetooth smart heart rate strap
Bluetooth smart cadence / speed
Bluetooth smart power meter
Features 
Power meter compatible
Recording interval
Virtual partner
Biometric altimeter
Compass
Electronic gear shift display
Live tracking
Strava live segments
Temperature display
Display GPS & sensor data
Shock resistantYes
Wireless connection
Smart notifications
Automatic sync
OtherThis is a simple but potentially life saving device. The ICEdot Crash Sensor straps on to your helmet to detect life-threatening impacts and send an emergency message through your smartphone to someone who can get you medical help. An alarm will sound on the phone, giving you a chance to stop the distress signal from going out if you’re ok. If you don’t stop the app, it sends an SMS text message to your pre-specified emergency contacts with your GPS coordinates.
Links 
View onAmazon
Amazon US rating3.7 out of 5 stars