This Medium size yarn swift is made of solid wood and finished by extra fine sanding (no toxic varnish fume). The Medium size can hold skeins up to 6-ft in circumference. It spins smoothly and makes yarn winding a fun job. The clamp-on base allows it to be firmly fixed at the edges of tables, chairs, benches, or any other convenient locations. It fits edges up to 1-3/4 inches thick. The craftsmanship on this yarn swift is superb.