Abstract: A portable self-contained milk flow indicator is provided for dairy barn applications. The milk flow indicator consists of a milk sensing device, a timing and switching circuit, indicators of the condition of milk flow, and a rechargeable battery, all sealed in a self-contained portable unit which can be used at any point in the milk line of a conventional dairy barn milking operation. The indicator is also provided with a battery charger which can be mounted on the wash manifold of a dairy barn milk house so that when the indicator is placed on the wash manifold for cleaning the battery, housed in the indicator, will automatically be recharged.