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WR 148 (HD 197406) is an extreme runaway system considered to be a potentialcandidate for a short-period (4.3173 d) rare WR + compact object binary.Provided with new high resolution, high signal-to-noise spectra from the Keckobservatory, we determine the orbital parameters for both the primary WR andthe secondary, yielding respective projected orbital velocity amplitudes of$88.1\pm3.8$ km s$^{-1}$ and $79.2\pm3.1$ km s$^{-1}$ and implying a mass ratioof $1.1\pm0.1$. We then apply the shift-and-add technique to disentangle thespectra and obtain spectra compatible with a WN7ha and an O4-6 star.Considering an orbital inclination of $\sim67^\circ$, derived from previouspolarimetry observations, the system's total mass would be a mere 2-3M$_{\odot}$ , an unprecedented result for a putative massive binary system.However, a system comprising a 37 M$_{\odot}$ secondary (typical mass of an O5Vstar) and a 33 M$_{\odot}$ primary (given the mass ratio) would infer aninclination of $\sim18^\circ$. We therefore reconsider the previous methods ofderiving the orbital inclination based on time-dependent polarimetry andphotometry. While the polarimetric results are inconclusive requiring betterdata, the photometric results favour low inclinations. Finally, we compute WR148's space velocity and retrace the runaway's trajectory back to the Galacticplane (GP). With an ejection velocity of $198\pm27$ km s$^{-1}$ and a traveltime of $4.7\pm0.8$ Myr to reach its current location, WR 148 was most likelyejected via dynamical interactions in a young cluster.

WR 148: Identifying the companion of an extreme runaway massive binary