The BESIII Collaboration has observed a candidate for a $c bar c s bar u$ tetraquark $Z_{cs}$ at $(3982.5^{+1.8}_{-2.6} pm 2.1)$ MeV and width $(12.8^{+5.3}_{-4.4} pm 3.0)$ MeV, while the LHCb Collaboration has observed a $Z_{cs}$ candidate in the $jpsi K^-$ channel with mass of $(4003 pm 6 ^{+4}_{-14})$ MeV and width $(131 pm 15 pm 26)$ MeV. In this note we examine the possibility that these two states are distinct eigenstates of a mixing process similar to that which gives rise to two axial-vector mesons labeled by the Particle Data Group $K_1(1270)$ and $K_1(1400)$. The main point is that on top of a $bar c c$ pair, the $Z_{cs}$ states have the same light quark content as the $K_1$-s. In the compact tetraquark picture this implies several additional states, analogous to members of the $K_1$ nonet. These states have not yet been observed, nor are they required in the molecular approach. Thus experimental discovery or exclusion of these extra states will be a critical test for competing models of exotic mesons with hidden charm.
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