In this paper, symmetric perturbation-based extra-insensitive input shaper (SPEI-IS) is newly proposed based on the impulse-time perturbation method. The proposed input shaper is devised by multiplying two input shapers in Laplace domain, of which the impulse-times are slightly perturbed from the ZV shaper, which results in a hump in its sensitivity curve. Different from the PEI-IS introduced by the same author, the SPEI-IS has symmetric notch points to enhance the robustness especially in low frequency range. For its usability, an explicit solution will be presented using Taylor approximation.