The nautilus evo abdominal is a true abdominal crunch machine that will push you to your limits and help you on the way to making your fitness goals a reality the four bar linkage system on this machine provides the user with rotation that simulates the same axis rotation as the body s natural axis massively increasing the safety for the user user s of nautilus equipment will feel immediate smooth resistance and proper muscle loading through complete range of motion like all of the evo rang