My office at work has an electric stapler that like any stapler, periodically jams. In order to clear it, an included clockwork key is used to manually advance the mechanism. However, the key went missing and the manufacturer (Swingline) does not offer replacement parts. (A new stapler would cost ~$USD 200.)
Thus, I reverse-engineered a different key for the same model to create a replacement.
This was created for the model 520e stapler, but should also work in its replacement, the 50201 and 50204. As this is an entirely functional part, it's not patentable and hereby released into the public domain.