Special Order Birkins, or Horseshoe Stamp (HSS) as they’re often called, are a category unto themselves. The opportunity to special order a Birkin is only offered to top clients, and the implication is that this Birkin could be an entirely unique combination. The Sellier style with external stitching and a sharp-edged structure is an exceptionally elegant handbag. This Sellier Birkin 25 is primarily crafted of Epsom leather, this printed leather takes its name from a town in south-east England that is famous for its horse races.