Wheels Mfg Headset Cup Press is a robust, and easy to use tool made up of two machined aluminum handles, 1/2" threaded rod and two machined aluminum drifts.
One drift is machined with multiple steps to fit common head tube inner diameters listed in the Compatibility tab below.
The other drift had two sizes to press in cups with either 1-1/8" or 1-1/2" bearings, but may be used for other cups with odd sized sealed bearings.