Techrite Controls Australia...
The RB 1700 & RB 1800 series feature 3/4, 1 (RB 1700) and 1 1/2 (RB
1800) sizes. The 3/4 size is specially designed for high pressure
reducing applications, such as LPG first stage pressure reduction, while
the 1 and 1 1/2 sizes are appropriate for Commercial & Industrial
applications such as burner and large appliance regulation, where fast
response is required. Their balanced valve design provides constant
outlet pressure under all inlet pressure conditions.