The heater/sensor is comprised of an adjustable thin-film heating band which surrounds 3/4 of the diameter of the upper region of the central retracting tube of the objective. A surface probe thermal sensor positioned in the gap formed between the ends of the heating band measures the temperature of the objective. This heater/sensor assembly is supported on an adjustable metal mounting to fit objectives ranging from 17 to 35mm in diameter. The heater loop requires a minimum of 3.5 to 6mm longitudinal, physical contact with the cylindrical objective surface depending on which objective heater is required. In some cases there may be a decorative collar on the objective which must be removed in order to permit adequate surface contact.
For full web page, please see http://www.autom8.com/temp-obj-heating.html
Download a brochure at http://www.autom8.com/pdfs/temperature/Objective-Heat-Cool.pdf