This is a great looking ring that is also safer than a metal ring if worn around electrical or mechanical equipment.  It is composed of 3 laminations of wood for strength.  The surface is sealed, but as with any wood product will do better if not immersed in water.  Water tends to displace the oil  in the wood, so can dry it out.  The ring can be waxed like fine furniture.  The rings shown are 8mm wide.