This is a homebrew cassette made out of various Shimano cassette parts.
This cassette was likely invented by its previous owner to adapt Uniglide cassette cogs onto a Hyperglide freehub.

This cassette was never officially offered by its manufacturer; use your judgement when putting this cassette into service as a single assembly. However, it is composed of parts that are all in great condition with no damage compromising their rideworthiness and no scuffs or scrapes inconsistent with used bicycle parts.