A surface mount coupler device is provided having a device body with a plurality of terminations located thereon. The coupler device is particularly useful in high frequency circuits to provide coupling between two circuit lines without direct electrical contact. For example, the device may provide coupling between a feedback control loop and an amplifier output section in a RF transmitter. The device body is built up on a rigid insulative substrate. During manufacture, one or more layers of insulative polymer are applied to the insulative substrate. The insulative polymer defines conductor channels in which primary and secondary conductors are located. The primary and secondary conductors are electrically connected to a respective pair of the terminations located on the device body. A sealing cover, preferably glass, is located above the polymeric insulative layers.