Thickness of Acrylic tank

[MartyB]

Posting for a friend - what do you think?

I have this option to buy a used Acrylic tank. I love the specs but the thickness has me a little uncertain. Here is what is being stated:
8'x3'x34"tall
Its 1/2" thick with a full peice on the top with 3 large areas cut out for acess for the inside

Everything I have read states that a tank this size should be more than 1/2 inch thick.

Please advise, thanks.