An Optional velcro strap in black or grey was made available – these straps attached to the main male hyperlink with the bracelet. The good news is, The material strap in the IW3715-36 along with the alternate rubber strap within the IW3548 match the Aquatimer! Rolex can make in excess https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/