\begin{table}%t5
\caption{\label{tab5}Summary of confirmed and candidate WNLh binaries  in young open clusters.}
\par
%\centerline
{\begin{tabular}{cccccc}
\hline
\hline
 Cluster  &Age &  Total &RV      &\multicolumn{2}{c}{Binaries} \\
         & (Myr)&       & survey &     Confirmed & Candidates \\
\hline
NGC3603    &1.3~$\pm$~0.3  & 3  & 3 & 2       &    0 \\
Carina     &1.5~$\pm$~0.5  & 3  & 3 &2       &    0 \\
HM-1       &2.2~$\pm$~0.5  & 2  & 0 &$-$       &    0 \\
NGC6231    &2.7~$\pm$~0.5  & 1  & 0 &$-$       &    0 \\
Arches     &2.5~$\pm$~0.5  & 13 & 0 &$-$       &    3 \\
Wd 2       &2.6~$\pm$~0.2  & 2  & 1 &1       &    1 \\
Bochum 7   &2.8~$\pm$~0.5  & 1  & 1 &1       &    0 \\
R136/30 Dor&$>$2         & 23 & 23& 8       &    1 \\        
\hline
Total      &             & 48 & 31& 14      &    5 \\
\hline
\end{tabular}}
\medskip
\par
The cluster list 
follows that of Crowther et~al. (\cite{PAC}), supplemented with the WNLh rich Arches (Figer et~al. \cite{figer2002})
and 30 Dor (Walborn \& Blades \cite{nolan}) clusters.  Column 4 summarises
 the number of stars in each cluster for which a RV survey has been carried out. Confirmed binaries were
identified via photometric or spectroscopic evidence, while candidate binaries were selected if  
$L_{\rm x} \geq 10^{34}$~erg~s$^{-1}$ and/or $kT >4$~keV, noting that such strict criteria 
would exclude known spectroscopic binaries such as WR20a and WR22 (Table~\ref{tab4}).
Given the different sensitivities of current  RV and X-ray surveys  (e.g. Pollock \cite{pollockE}; Pollock et~al. 
\cite{pollockR}; Ignace et~al. \cite{ignace}; Oskinova \cite{oskinova}) 
we present results for individual clusters.
\end{table}