The Air Pressure Pro nitrous bottle regulator is the best way to control nitrous bottle pressure.
It eliminates excessive purging keeping more nitrous in your bottle for better performance and your outlet pressure consistent for accurate tuning.  Adjustable from 200-1100 psi  - Works on any nitrous system, wet or dry. Flows 125hp @ 900 psi   - 1/8 NPT inlet and outlets Gauge port 90 Degrees from outlet. Heavy Duty Adjustment Cap Stainless Adjustment Screw and Washer