Abstract: A pressure regulating valve including a seal seat that defines an opening. A seat stem is moveable between a closed position in which the seat stem engages the seal seat and prevents fluid flow through the opening, and an open position in which the seat stem is spaced from the seal seat and permits fluid flow through the opening. A biasing element biases the seat stem in the closed position. A housing defines a passage that extends between an inlet and an outlet. The seal seat, seat stem and biasing element are positioned in the passage such that movement of the seat stem between the closed and open positions controls flow of the fluid between the inlet and outlet. The housing has an outer wall including a coupling mechanism for fixing the housing inside a channel of a primary regulator body.