Type in the values of the stamps that you have.
You will be shown the combinations of stamps
that add up to the postage due.
This program may run slowly in certain browsers.
Your stamp values will be saved for the next time you return, if you
have cookies turned on.
Try manually inserting repetitions to customize your usage of stamps.
This old Westinghouse klystron vacuum tube on a breakout socket reminded me of Robert Kinoshita's Robot B-9.