When they said "firm", they used the word incorrectly in regards to this product. "Firm" to me means something comparable to the waffle-type, somewhat flexible mattresses and pads. In reality, this is a stiff mat and is basically a hard surface albeit with a cover. It was my intention to lay this on my senior Rottie's cushy bed to help her out with stiff joints. The hard surface and inflexibility of the mat make this a less than comfortable bed. If you are just laying this on a hard floor to use, it would be perfectly fine but there is no cushioning support for old and aching joints. I'm sending it back!