Our Neighbor has a classic Collie Dog that was injured and couldn't jump down from the bed. So they were shopping for a ramp. As this was a quite expensive dog, and was being trained as a hospital, nursing home therapy dog, we ended up drawing up a ramp that could be "reversed" to enable placing on either side of the bed. Built from Beech and in knock down style this is what was decided on. the basic structure is put together w/ Kreg screws and the side rails have dowels, enabling them to be removed and put on either side. The end rail is permanent. We originally placed carpet on the ramp, but the dog would slip on the carpet, so it was changed out soon after delivery for a wide adhesive backed sandpaper covering. They said it took about a week to get the dog comfortable with it, but she uses is regularly now.