A test and measurement device measures an insertion loss of a material under test. The test and measurement device includes a reference device in contact with a first surface of a material under test, the reference device including a reflective component and an absorbing component. A testing device is in contact with a second surface of the material under test, opposite the first surface. The testing device includes a first transmitter to output a first signal at a predetermined frequency to the reflective component of the reference device through the material under test, a first receiver to receive a first reflected signal from the reflective component, a second transmitter output a second signal at the predetermined frequency to the absorbing component of the reference device through the material under test, and a second receiver to receive a second reflected signal from the material under test.