15" sisal rope cat scratching post FREE SHIPPING !!!! Strong but lightweight (to minimize shipping costs) construction. Removable wood cap so you can add rocks, sand or any heavy material (do not use water) for extra stability. Ships in 2 parts all you need is a Phillips screwdriver to tighten the 4 x ¼ inch bolts. The Sisal rope is tightly wound using no glue. The only glue I use is on the top and bottom of the post. The wood base has 4 Antiskid rubber pads. No staples were used in the construction of this post.N 1. 13.