I have an Ashley APS-1600 wood stove, brand new NOS, that I just finished installing. The last component I need is the two "isolator" pads that go above the bricks at the top, which I believe is called the "baffle". The manual does not identify either the material nor the thickness, just the length and width (9.5" x 12"), qty 2. Is this just a ceramic or mineral fiber pad, or are they vermiculite boards? What thickness goes there? The stove is the same as the Drolet HT-1600 and many others. The OEM is Warnock Hersey who is apparently not in business anymore.