configuration and an outer toroidal configuration. In addition, the analysis of the variation of “magnetic vectors” (hereafter, $\overrightarrow{B}$-vectors) position angles (PA) led the authors to also consider the possibility of an helical magnetic field geometry. All the detected features seem to point towards a magnetic collimation and launching mechanism in OH 231.8+4.2.\
Thus, in this article we present new high resolution polarimetric observations (at 0.5) obtained with the Atacama Large Millimeter/submillimeter Array (ALMA). These data provide new insights into the inner dusty region of OH 231.8+4.2 by allowing us to probe the magnetic engine (assuming a dynamo mechanism) closer to its launch-site and complete a multi-scale analysis of the magnetic field in OH 231.8+4.2. We present the ALMA observing procedure in §\[obs\] and the results are shown in §\[cont\]. A comparative analysis with all the previously obtained data is presented in §\[comp\] & §\[comp2\]. Our concluding remarks are shown in §\[final\].

![ALMA dust continuum emission map, at 345 GHz, of OH 231.8+4.2. The global hourglass shape is well defined and the peak emission is coincident with the central star location (CS on the map). The origin (0,0) of the map corresponds to the coordinates $\alpha(J2000)$=$07^{h}\,42^{m}\,16^{s}\,947$, $\delta(J2000)=-14\degr\,42\arcmin\,50\farcs199$. North is on top 