This specialized tool is used to open and close the piston stem and flange of the Sherwood SR series first stage.
 
The tool can be used in two different ways.
Removing and Installing the SR1 First Stage Seat Retainer
It can also be used to install the piston stem and flange of the SR 1 first stage.
 
The best way to do this is to make sure you have clamped the first stage in a vise with a first-stage holder. You now have both hands free to hold the piston flange with the tool and remove or install it from the other side with an alan key.
If more force is needed the tool can be held by an 17mm Open end spanner, Socket, or Adjustable spanner. 
 
The tool is precision machined from stainless steel.
 
GTIN: 8720828266762