Fashion designer Rick Owens has updated three sandal designs by footwear brand Birkenstock, using a combination of felt, pony hair and grainy leather.
The collaborative collection sees three classic sandal styles from Birkenstock's main line ? the Arizona, Madrid and Boston ? updated in Owens' typically monochromatic colour palette.
Each of the shoe designs is available in four different finishes, including pony hair, full-grain leather and felt.

The collection marks the first time Birkenstock has invited an individual designer to collaborate on its Birkenstock Box project, which sees a pop-up space travel to different global cities, to allow the brand to work alongside selected retailers.
Previous locations visited by the brand include Berlin with retailer Andreas Murkudis, New York with Barneys and the Whitney Museum, and Milan with concept store 10 Corso Como.
For this edition of the Birkenstock Box, Owens has also rehauled the mobile structure, which is made from two shipping containers, stacked on top of one another.
The mobile space now features a white exterior and a neutral interior, which the designer based on his own store in New York.
Ahead of the collection's launch in March, the shipping containers will be placed in front of Owens' Los Angeles store, which opened in 2015 and features interiors inspired by the imagery of religious films.

As well as selling the new styles, it will stock a selection of Birkenstock's main lines, and furniture and accessori...