The types and sections of wood are selected for their durable characteristics, resistance to termites, and high density - which permits a highly polished finishing without varnish or stain. Not a single endangered tree was destroyed for their manufacture. The standard Mechelen (also known as "Mechlin") bobbins are approx. 4 1/4 inches long and the Delicate Fine Mechelen bobbins are approx. 3 3/8 inches long.