The Skyfort with Tube Slide is made from 100% cedar. With small, tight knot structure, your lumber will be less likely to develop small cracks emanating from knots. All lumber is pre-stained for a smooth and clear appearance, as well as cut and stamped with the part number to help speed up the building process. Some pilot-hole drilling may be required. Our exclusive Safe-T-Fuse hardware makes assembly easy and secure. Its laminated swing beam is built strong, with steel clam-shell brackets to ensure that swinging is always safe.