Pressure valve screw for older style Smart Parts Max Flow

[chuckwood]

Hi all,

I have a max flow regulator and the bottom screw has disappeared which I believe is the pressure valve screw? It is an Allen key style screw and I have included photos of the reg in the hope that someone knows what the heck I am talking about.
The missing screw is situated next to the on/off lever underneath the reg itself. The photo enclosed shows the hole where the screw should be.
All help greatly appreciated as I want to get this fixed a.s.a.p.

 

[bobby boy]

max flow

i have an old one i do not use any more you can have it for 10.00 the reg plus p&p

 

[chuckwood]

Thanks bobby, if no one else can help I will take it off you.
Cheers.