Tank setup safety issue

[IfoundNemo]

I just got a 75 gal tank for free. I Filled it up with water. No leaks within the past seven days. However, the tank does not have a plastic support bar in the middle top rim like mine does. I'm assuming this maybe an older model tank... Do any of you have a tank like this, and would this tank be ok to use? TIA

[malkore]

Well, is it an old tank?
measure the thickness of the glass. some old tanks have thicker glass and didn't have a center brace.

[IfoundNemo]

Its a used tank made by Oceanic. The glass is 1/2" thick like mine, accept it doesn't have a center brace.