The IWC Aquatimer IW3568 was introduced in 2009. It features a stainless steel case of 44mm, which is water resistant up to 200 bar and fitted with an external rotating bezel. In 2011 the collection was updated with minor changes to the bezel mechanism, while the optional bracelet got a full-brushed finish.
The references for the straps and bracelet are per the following;
IWA31757: stainless steel bracelet, polished center links
IWA55585: stainless steel bracelet, fully brushed
IWA31758: rubber strap standard size
IWA31760: rubber strap XS
IWA31759: rubber strap XL
IWA36516: velcro strap standard size
IWA36517: velcro strap XL (320mm)
The associated pin buckle is ref. IWA34456.