Super Muscle evolved from Muscle:

Light, precise, reliable, intended for professional and long-distance use. Through the use of Kevlar, High Modulus Carbon and Nickel, Columbus has further reduced the weight (-15%) and improved performance characteristics.

The chain stay was built with the *single plug* concept that confers the stay with considerable resistance to torsion, and much easier assembly versus the original Muscle version with 2 individual chainstays.

NOTE: THIS IS JUST THE CARBON STAYS AND DROPOUT, THE BOTTOM BRACKET AND SEAT TUBE SOCKET ARE NOT INCLUDED.