The Birkenstock Betula Mia Flat comfort Sandal in Black Leather for women in size 40 offers a stylish yet comfortable option for everyday wear. With a slip-on closure and low heel height, these sandals feature a solid black color and the signature Birkenstock comfort features. The Mia sandals are designed for women with a US shoe size of 9, making them a versatile choice for any casual outfit. Made of high-quality leather, these flats are a timeless and practical addition to any wardrobe.