This paper presents a four-dimensional (4D) autonomous chaotic system. The new system is obtained by introducing the state feedback and a novel n-well potential function to the third-order Duffing system. The proposed potential function enables us to create butterfly wing chaotic attractors. The new system can generate n-scroll and 2n-butterfly wing chaotic attractors. The basic dynamical behaviors and properties of this system are investigated, such as equilibriums, stability of equilibrium points, attractors, and Lyapunov exponents. The circuit realization and experimental results are also presented.