Magnolian High Efficiency DC/DC Converter 12V Step Down to 9V 2A 18W Power Supply Module,Waterproof All epoxy sealed containers with Waterproof Housing; Non-isolated High efficiency: &gt;96%; Reliable, low heat dissipation With overload / over-current / over / low voltage protection, stable performance Light compact, convenient to use and transport; Auto recovery Widely used in Car device, such as LED Display, Hard Disk Player, MP3, DVD, GPS, etc