Garmin Descent T2 Transceiver Black. Enhanced SubWave sonar technology lets you monitor up to 8 tanks when under water viewing air pressure depth use rate and time remaining for multiple types of diving. Plus you can even communicate via preformatted messages (coming soon) with other networked buddies wearing their Descent Mk3i dive computers. Specifications for Garmin Descent T2 Transceiver: Manufacturer: Garmin Color: Black Battery Type: Lithium Metal CR123A Battery Life: 100 hours Dimensions: 3.33 x 1.44 x 1.44 in # of Antennas: 3 Features of Garmin Descent T2 Transceiver Compact dive accessory attaches to high-pressure regulator ports without interference from hoses Built to withstand the elements the Descent T2 transceiver is dive-rated to 20 ATM (see Garmin.com/waterrating) so you can dive deeper without worry Get tank pressure air time remaining and air consumption rate sent directly to paired air-integrated Descent dive computers (sold separately) for enhanced situational awareness For improved communication exchange preformatted diver-to-diver messages with other Descent T2 transceiver-networked buddies wearing SubWave network-compatible air- integrated dive computers up to 30 meters away (available with software v.15.70 or later) Pair up to 8 transceivers with each compatible air-integrated Descent series dive computer (sold separately) within range so you can dive with multiple tanks or monitor your dive buddies air levels and depths up to 10 meters A simplified pairing process using BLUETOOTH Low Energy wireless technology makes it easy to identify your buddies names with the Descent T2 transceivers theyre wearing Descent T2 transceiver battery life: up to 100 hours of diving with a user-replaceable CR123A lithium battery Package Contents: Garmin Descent T2 Transceiver Air spool Documentation Garmin 010-13308-00: Descent T2 Transceiver Black