You can do this:
((get-counter -counter '\\rmfvpc\TCPv4\Connections Established').countersamples) | % {$_.CookedValue}
and this:
(get-counter -counter '\\rmfvpc\TCPv4\Connections Established').Readings | findstr ^[0-9]
and this:
(get-counter -counter '\\rmfvpc\TCPv4\Connections Established' -continuous -sampleinterval 2)
but you can't do this: