Designer Nappa Leather Slides For Women Foldable Flat Heeled Catwalk Black Sporty Matelass Nappa Leather Sandals Miu Miu Matelass nappa leather Devotion sandals Designer Nappa Leather Slides For Women Foldable Flat Heeled Catwalk. Miu Miu's matelass nappa leather Sandals are distinguished by the matelass work that gives a three dimensional effect to the upper. The design is embellished with metal lettering, while the leather sole and banded leather heel complete the model with elegance and attention to detail.