Brand new! Only 6 miles in them. I need a smaller size and can’t return them. The adidas adizero Boston 12 is a high-performance daily trainer that has been upgraded to offer a more comfortable and faster ride. The highlight of the Boston 12 is found in the midsole where we see a carefully crafted setup that increases both the shoe's softness and speed. The top layer is made of Lightstrike Pro, which is the brand's lightest and softest foam, while the frame is made of the slightly denser Lightstrike 2.0 foam that helps to maintain a stable and smooth ride at any speed. Sandwiched between the two layers is the ENERGYRODS 2.0 system, which comprises split rods that provide a snappy and energetic toe-off while allowing for flexible foot movement