Heating Mantle – Top. Has Connector for Power Cord. Lined with mesh fabric that is stitched to padded silver material. Openng meaduring 16 cm L x 4 cm W. Metal plate on side – GLAS – COL Made in U.S.A. U.S. Pat.2,231.506. GLAS-COL Apparatus Co., Inc., Terre Haute, Ind. Ser. No. 80787 Volts 110.