Suunto D4 manual Free dive time limit

6.3.2. Free dive time limit

The FREE mode has a time limit of 10 minutes. After 10 minutes, Suunto D4 will automatically change from free dive to scuba bottom timer. After the dive, the no-fly time will countdown from 48 hours. Also, you will not be able to dive in AIR or NITROX modes until the no-fly time has counted down to zero. You can only set the Dive mode to OFF.

NOTE	If you want to dive in AIR or NITROX mode after diving in FREE
	mode, remember to switch to the correct mode. Otherwise, the
	free dive time limit will activate after 10 minutes.

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