  For the first time, the pair production of the heavy charged gauge bosons,
known as $W'$ bosons is considered, when both decay to $\tau$ leptons. The
reported detailed efficiency of object/event selection by the CMS experiment is
used to find the lower limit on the mass of $W'$ boson. Various assumptions for
the coupling of the new gauge boson are examined and the results are reported.
In the case of a SM-like $W'$ boson, masses below 290 GeV are excluded at 95\%
confidence level. The method can be used to constrain the new models with the
similar final state.
