A line splitter is a essential piece of gear for anyone interested in how much power a appliance is drawing. They allow you to measure power consumption and voltage while shielding you from the 120VAC line voltage. This unit has two square holes for use with a clamp-on amp-meter.  One hole is for measuring the current as-is (i.e. 1x), while the other hole has the hot wire looped around it 10x inside, allowing you to make more sensitive measurements with the current clamp.