... reliably measures the thickness of the poured concrete slab of non-metal like structure,concrete,wall,girder,bar,pole,wood and ... source:Host 9VDC(6 AA battery),Transmit electrode 9VDC(Internal high-capacity lithium battery)Host dimension:270×150×45(mm)Transmit ... ×80mmExtension Bar:φ25×600(mm)(3 piece)Work PrincipleDJLC-A concrete thickness gauge is composed of signal transmit, connector, signal ...