The results of X-band measurements on GaAs power f.e.t.s are reported. These devices are fabricated with a simple planar process. Devices with output powers of 1 W or more at 9 GHz with 4 dB gain have been fabricated from more than a dozen slices. The highest output powers observed with 4 dB gain are 1.78 W at 9 GHz and 2.5 W at 8 GHz. Devices have been operated with 46% power-added efficiency at 8 GHz.