The Garmin Descent MK3 Dive Computer Series has sonar capabilities
Amazon.com: Garmin Descent Mk2i, Watch-style Dive Computer with Air Integration, Multisport Training/Smart Features, Titanium with Black Band : Electronics
Hands-on: Garmin's New Descent MK1 Diving Watch | DC Rainmaker
Descent™ Mk2 - Silent Explorers
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Descent MK2S - Jupiter Dive Center
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