Identifying Old Master Lock Hasps

[llr1234567890]

I accumulated these Master Lock Hasps off of old filing cabinets, however they are significantly different from the common Master hasp I am used to. These are much more substantial (thicker and harder steel), and have a stronger hinge. However, I cannot seem to find any information on them (model, manufacture date range), and was wondering if anyone here has ever come across these.

http://imgur.com/a/CYovh

[Squelchtone]

[EDIT: Moved from Locks to Ask a Locksmith - This Old Lock]

[billdeserthills]

I accumulated these Master Lock Hasps off of old filing cabinets, however they are significantly different from the common Master hasp I am used to. These are much more substantial (thicker and harder steel), and have a stronger hinge. However, I cannot seem to find any information on them (model, manufacture date range), and was wondering if anyone here has ever come across these.

http://imgur.com/a/CYovh

I probably have a few laying around in my shop, I guess my Dad bought them 30 or so years ago. The way the word Master is incised
is a good giveaway as to the age. You can probably ask folks at antique-locks.com, someone may know over there