VLBA total (contours) and polarized (color scale) intensity images of Mrk 421 at 43 GHz. The peak of the total intensity is 295 mJy beam⁻¹. Yellow linear segments within the images indicate the direction of polarization, the black horizontal line marks the position of the core, A0, and colored circles indicate locations of jet features A1 (blue), A2 (gray), and P (red). Images are convolved with the same elliptical Gaussian beam, which is shown in the bottom-right corner by a black ellipse.