Fitting a New pressure Gauge needs some care to be taken to get it to seal and also so you don't crack the head of the filter valve. I show you how here.
Mark's Reviews & Tutorials
How to Instal a Pool pressure gauge. Fit metal to plastic parts old swimming pool spa
Affiliate Links to Buy:
Oil Filled Pressure Gauge for Pool or Spa:
This one has the right colour coding and thread size and stainless steel body
Genuine Hayward gauge: