An Optional velcro strap in black or gray was provided – these straps hooked up to the primary male backlink from the bracelet. Luckily, The material strap with the IW3715-36 along with the alternate rubber strap within the IW3548 match the Aquatimer! But it surely appears to be the variable https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/