A heating device comprising: a tubular body having a passage therethrough and through oppositely-disposed ends of the tubular body, the tubular body comprising at least an inner layer surrounding the passage and an outer layer surrounding the inner layer, the inner layer being electrically resistive and the outer layer being electrically insulating, the passage being sized and configured to removably receive therethrough a tubing; electrically-conductive first and second collars secured at the oppositely-disposed ends of the tubular body and functioning as electrical contacts for the inner layer, each of the first and second collars comprising a first tube received in the passage and surrounded by an end of the inner layer at one of the oppositely-disposed ends of the tubular body and a second tube surrounding the end of the inner layer and crimped onto the first tube to sandwich the end of the inner layer therebetween; a temperature sensor coupled to the tubular body to monitor a temperature of the inner layer at a location along a length the inner layer between the first and second collars, the temperature sensor having a junction tip that is located between the inner layer and the outer layer and electrically insulated from the inner layer; a cord connected to the temperature sensor and exiting the tubular body; and contact leads located at the oppositely-disposed ends of the tubular body, each of the contact leads being electrically connected to one of the first and second collars and configured to functionally couple with a power source to provide an electrical current to the inner layer, wherein applying an electrical current to the inner layer increases the temperature of the inner layer. a tubular body having a passage therethrough and through oppositely-disposed ends of the tubular body, the tubular body comprising at least an inner layer surrounding the passage and an outer layer surrounding the inner layer, the inner layer being electrically resistive and the outer layer being electrically insulating, the passage being sized and configured to removably receive therethrough a tubing; electrically-conductive first and second collars secured at the oppositely-disposed ends of the tubular body and functioning as electrical contacts for the inner layer, each of the first and second collars comprising a first tube received in the passage and surrounded by an end of the inner layer at one of the oppositely-disposed ends of the tubular body and a second tube surrounding the end of the inner layer and crimped onto the first tube to sandwich the end of the inner layer therebetween; a temperature sensor coupled to the tubular body to monitor a temperature of the inner layer at a location along a length the inner layer between the first and second collars, the temperature sensor having a junction tip that is located between the inner layer and the outer layer and electrically insulated from the inner layer; a cord connected to the temperature sensor and exiting the tubular body; and contact leads located at the oppositely-disposed ends of the tubular body, each of the contact leads being electrically connected to one of the first and second collars and configured to functionally couple with a power source to provide an electrical current to the inner layer, wherein applying an electrical current to the inner layer increases the temperature of the inner layer.