Two vapotrons from the JET actively cooled divertor design have been fitted by JAERI with unidirectional high conductivity CFC tiles and have been tested in the JET Neutral Beam Test Bed. The test section showed excellent uniformity and accepted power densities up to 30MW/m2 for equilibrium pulses. The surface temperature was 1100°C at 20MW/m2. One tile detached at a power density of 25MW/m2. A total of just under 300 pulses at power densities mostly between 20 and 30MW/m2 have been fired onto the test sections without additional failure. The hydraulic parameters were: Water inlet temperature: 15–20°C, average water pressure in the component: 0.4 and 0.69Mpa, flow velocity: 6.9 and 7.5m/s