Very Soft and sturdy material. I have a older cat and a younger cat.The younger cat loves it. The older one won't go near it. Neither one use the house, but my younger cat loves the toy and top tier.It helps to have someone help you when putting it together.It does wobble a little when my cat climbs up, however it appears to be very stable and it doesn't bother her at all. Love this cat tree and very reasonable!