Abstract: A clamping apparatus for use with band heaters for heating nozzles of plastic extruding and injection molding machines to maintain intimate contacts between the heater and the cylindrical surface being heated as well as a clamping apparatus of general application for maintaining intimate contact between the apparatus and the cylindrical object to be clamped. The clamping apparatus comprises a generally cylindrical strap incorporating a heater mechanism, or without a heater mechanism therein, which includes end portions, at least one of which has an upstanding tab with one or more openings therein for receiving a ratchet clip which upon movement thereof, causes the interior of the cylindrical strap to tightly engage the generally cylindrical object to be clamped.