A non-compliant fiber-reinforced medical balloon comprises a first fiber layer and a second fiber layer embedded in a continuous matrix of thermally-weldable polymer material defining a barrel wall, cone walls and neck walls. The fibers of the first fiber layer run substantially parallel to one another and substantially parallel to the longitudinal axis. The fibers of the first fiber layer have a pattern of different lengths and are divisible into a first group and a second group based on length.