Diamondback Bicycles Calico ST Women's Dual Sport Bike, Blue High quality aluminum frame with forged dropouts is strong and durable for bumpy roads and potholes in your way Shimano 3x7 shifters give you 21 speeds to choose from Dual sport 700c tires are the same diameter as road tires that keep you rolling fast on pavement, but have enough width and traction for trail use Alloy linear v-brakes make stopping a breeze Women's specific frame is made to better fit women's dimensions