designed this help with air flow under my couch to alleviate mold or mildew build up and with possibility to store low profile objects under the couch. risers are designed to this particular couch with an ID of 61mm, they fit snug around the OEM footer. With the OEM one off it seems like it wont go down all the way but with pressure (sitting on the couch section) it with push the OEM all the way down inside the riser making the riser look like a factory made footer. it was supposed to be perfectly cylindrical but due to transfer of the file from shaper 3D to bambu the resolution changed to having the multiple sides look. I have some printed with 2 walls and others with 3 walls i haven't had any issues with either of the models. i also have some printed in PLA matte but majority in PETG.