Since I'm the seller of said timer, please let me 'splain...
I bought this timer taking a wild chance that it might work in my circa-1974 model W3T-22 Gold Crown 1-18, but it did not match (fewer circuits and one less notch in the stop cam). Since the basic construction of this timer is similar to the timer in the Gold Crown and given the lower part number, I figured it could be for an earlier, lower-end 1-18.
If anyone can cross-reference the part number (635245), please speak up. Thanks!