Need help identifying handcuff

Hello,

I ran across a set of old cuffs marked 91 with matching key. The only other marking I see is on the cuffs '2 1/2'

I'm not an expert by any means & so I'll leave it up to you guys for help.

Many thanks

For some reason the photos didn't load with the post. Not really sure how to add them although I did use photo bucket.