I don't know about the 4 port unit but this should do the job. It is a Penski Racing Shocks nitrogen filler.
I purchased just the tip for $48 + Tax + Shipping. You can buy this unit from:
Ask for Troy. Tell him what you want to do.
About 5 or 6 years ago, a fellow builder made a reference to a strut adapter
that was being built and sold commercially. The adapter has four ports and is
used to more easily get high pressure nitrogen into the gear struts. One of
the ports has a pressure guage attached to read the existing strut pressure,
one port is used to relieve pressure, one port is used to connect the device
to the gear strut schraeder valve and the fourth port is used to apply
nitrogen, or any other gas.
[Does anyone on the LML happen to know] the name of the company selling
this item.
regards,
Howard Kanner
Go Vertical LLC of PA
950 N Penn Street
Philadelphia, PA 19123
tel (215) 928 1800
fax (215) 928 1850
www.govertical.com