Parabolic springs have leaves with a tapered profile. ... This is the technical way to say that each parabolic leaf has the same shape & function of a complete multi-leaf spring – thick at the centre and thinner at the outer ends. The characteristic of parabolic springs is better riding comfort and not as "stiff" as conventional "multi-leaf springs". It is widely used on buses for better comfort. A further development by the British GKN company and by Chevrolet with the Corvette among others, is the move to composite plastic leaf springs.