Sleep Better 5-Inch Extra Firm Mattress Topper

It arrived folded length wise and rolled up in a box.
Once unpacked it took a number of hours to expand to it's full size.
The final dimensions were a bit less than 80x60x5 and not completely uniform.
Roughly the length was between 77 and 78", the width was around 59" and the height was around 4.5".

The mattress is manufactured by the Carpenter Company:
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The mattress feels nice and firm, but not harsh, and the material seems to be of decent density and quality.

I use this as the base layer of my "custom" mattress.
On top of it I have a 3" memory foam topper and I have it enclosed in an 8" velour zippered cover.
I've had it in use for a few days now, and it's wonderful.

This product arrived timely and well packaged. The price was reasonable and the foam itself is very firm, which is what I expected. But the stated dimensions were not accurate. The ad states, "Queen size measures 60 by 80 by 5 inches". The 60 and 5 were correct, but the length was 80 at one corner and tapered down to 77 inches at the other corner...not quite a rectangle that most people would expect for a bed. This is awful quality control! This worked ok for me as I needed to cut it down for a non-standard full bed, but for those of you who really need the stated size; BEWARE!!!

I bought this assuming that it would be firm mattress pad and would help my back. Initially when I got this, i was really happy. The topper was realy firm and was good support to my back but as I have used it over last few months, i feel the topper has lost it firmness.