This is a key i purchased from Sears Parts service a few years ago so that I would have a spare key.
The Item it went to has since been sold and I just stumbled across the spare key.
This key is used in several Craftsman, Husqvarna and Poulan mower models
Aftermarket replacement for OEM part 532180331
Additional part numbers are as follows: 532-180331 and 108331
Compare your key to the photos