  Invisible decays of neutral hadrons are evaluated as ordinary-mirror particle
oscillations using the newly developed mirror matter model. Assuming
equivalence of the $CP$ violation and mirror symmetry breaking scales for
neutral kaon oscillations, rather precise values of the mirror matter model
parameters are predicted for such ordinary-mirror particle oscillations. Not
only do these parameter values satisfy the cosmological constraints, but they
can also be used to precisely determine the oscillation or invisible decay
rates of neutral hadrons. In particular, invisible decay branching fractions
for relatively long-lived hadrons such as $K^0_L$, $K^0_S$, $\Lambda^0$, and
$\Xi^0$ due to such oscillations are calculated to be $9.9\times 10^{-6}$,
$1.8\times 10^{-6}$, $4.4\times 10^{-7}$, and $3.6\times 10^{-8}$,
respectively. These significant invisible decays are readily detectable at
existing accelerator facilities.
