Fan forced and features a heavy-duty heating element with large fin area for maximum heat transfer. High-quality nickel chrome wire is sealed in a steel tubular sheath. A simple field conversion to a tamper-resistant feature. Whisper quiet, vane axial fan that has proven to be successful in other products. Rough-in dimensions 19-15/16 in H x 14-3/16 in W x 4 in D. Surface mounting kit is not included. Decorator ivory finish. UL listed. Built-in single pole thermostat. Surface mounting kit can be purchased from the factory, No. 3310EX33R.