An Optional velcro strap in black or gray was offered – these straps connected to the first male hyperlink of your bracelet. The good news is, The material strap through the IW3715-36 plus the alternate rubber strap through the IW3548 suit the Aquatimer! The Royal Oak celebrates its 50th anniversary https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/