Suunto D4F Black Freedive Computer - Closeout!D4F Black Freedive Computer The same performance you've come to expect in the popular d4i scuba computer is now available in a version dedicated solely for freediving. the Suunto D4f Freediving Computer displays present and maximum depth of your dives, and logs them in its logbook history. This computer also calculates dive time and surface intervals, allowing you to perform better by getting sufficient breathe up time between dives. An apnea timer