Using Contains?

$SCCMSite = Read-Host "Which SCCM sit will this machine be a member of?  P01, P02, M01 or E01?"

If ($SCCMSite -eq "P01")

    {  $SITE = "\\BOSSMSP1\SMS_P01\Client\ccmsetup.exe"

    }

If ($SITE -contains 'SMS_P01')

    { 

        Write-Host "You picked P01"

    }

the above code runs without errors but if you enter P01 the Write-Host command never runs.     I've tried many different things on the IF line too.  What am I missing?