Avalanche Transceivers allow equipped skiers to rapidly locate others (similarly equipped) buried in an avalanche. An avalanche victim's chance of survival drops from 93% to 26% within the first 45 minutes of burial so a quick rescue by your companions is required.
I hope you will read the information and review linked to the right but for those who won't here is the very short summary:
Advanced digital unit with multi burial features.
Facewest Recommended for advanced users
3 antenna digital unit with advanced features.
Advanced 3 antenna digital transceiver.
3 antenna digital unit for the recreational user.
3 antenna digital transceiver.
3 antenna digital transceiver with masking.
Simple great value transceiver.
2 antenna digital transceiver. Very quick and easy searching
Single antenna digital transceiver. Only 110g.