Material: Made from Rubber for a durable and long lasting air tight and waterproof seal Easy Installation: Accurate Replacement part used to Replace the broken or damaged part! Perfect fit. You do not need a Technician to do it. Complete Set: Thickness: 0.5mm / Inner Gasket Diameter 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm (Each Size 50 Pieces) The Gasket can stretch several mm and can also be used for Watches with different shapes other then Round. Product provided by MMOBIEL - We always try our best to exceed your expectations at every turn. Join the ever growing list of satisfied customers and discover the difference with MMOBIEL.