The Sumlog® Transducer is required to measure boat speed through the water. The Sumlog® includes two paddle wheels which can be switched  to match the speed range of the boat, thereby supporting speeds from 0 to 18 or up to 50 knots respective of the installed paddle wheels. The NavBox supports up to two Sumlogs® which can be directly connected to the dedicated Sumlog® ports using a 4 pin M12 connector extension cable.

12 – 24 Volt