watch Harry Potter - Slytherin quality watch Harry Potter - Slytherin. Composition: strap made of synthetic leather, clock movement (powered by battery which is included in the watch). Total length of the watch - 21,5cm, for circumference wrist approx: max 18cm. Average watch max. 2,4cm. Packed in a gift box. watch Harry Potter - Slytherin - CRTTP000317 - Metal-shop