I recently purchased this 4 Step 28" Pet Stairs for my 8 year old dog who enjoys getting up in our bed to sleep at night.  By purchasing the stairs, I am hoping to slow down the wear and tear of her joints and bones.  The stairs comes assembled and all you have to do is pull the legs out and snap in place.  You also have to peel the paper back on the felt pads that stick onto each step.  The stairs are very stable and well built.  The only small complaint that I have is that my dog's paws slide on the felt pads while going down the steps.  This issue can be fixed by putting a better non slip surface on each step.  Overall, I believe that this was a well made purchase.