The document describes a radiator leakage tester that is ISO 9001 certified. It tests radiators at 138kPa for leaks up to 4.2cm by controlling temperature and pressure. The tester uses flexible fixtures to accommodate different radiator models and sizes. It constructs the instrument with stainless steel and pneumatic controls for loading radiators, imparting controlled air pressure, and displaying pressure holding time. It can test radiators ranging from 300mm to 1000mm.