Rapport Watch Winder Quantum Quad Four Leather Grey W624. We've combined the latest technology and premium leather to create our Quantum Quad Watch Winder. The Quantum watch winders represent our exclusive range of leather wrapped watch winders. The Quantum Quad will keep your four watches ticking and in pristine condition when you're not wearing them. We have sourced a quintessential metallic leather which covers the external case, with a velveteen interior lining.