Genuine SVIG Ghiblis soling material. Made in Italy. These are rectangular cut that you trim to fit for the Birkenstock size requested and 10 MM thick. Trimming and sanding may be required after application. Colors available are Black, Brown, Beige and White with the traditional dog bone design. Soles are approximately 10mm thick. The Ghiblis compound is microcellular rubber that according to the SVIG website is a well-performing compound, extremely light, flexible and anti-slip. We love the SVIG line of products.