The MUltiple Critical ROot MAximally Flat (MUCROMAF) polynomials are defined. Their behavior is maximally flat at the origin (as the classical Butterworth polynomials), while the multiplicity of the critical root pair (the nearest to

-axis) is higher than one: then the polynomial degree is higher and the critical root pair

-factor is lower than those of the analogous Butterworth polynomials. Thus they are useful to approximate the RC active-filter pattern without finite transmission zeros and with low sensitivity.