A check valve , comprising: a liner , the liner defining a flow passage aligned along a longitudinal axis defined by the liner , the flow passage having an inlet portion and an outlet portion downstream from the inlet portion relative to the direction of the flow of fluid through the flow passage ; a poppet , the poppet having a first flow face and a second flow face , wherein an axially extending sidewall of the poppet is interposed between the first and second flow faces ; and a biasing element operably coupled between the poppet and the liner to bias the first flow face against an annular seat defined by the liner in a closed position of the check valve ; wherein the poppet is movable from the closed position to an open position wherein the poppet is unseated from the annular seat and from the open position to a full open position, wherein in the full open position an entirety of the axially extending sidewall is downstream relative to the direction of fluid flow through the flow passage from a downstream edge of the outlet portion ; wherein a radial clearance is formed between the axially extending sidewall and the outlet portion of the flow passage such that a leakage flow is permitted from the inlet portion through the outlet portion in the open position; wherein the poppet comprises a stem leading to a head and wherein, prior to unseating, fluid pressure acts on a portion of the first flow face of the head of the poppet ; and wherein the portion of the first flow face is defined radially between a radial inner face of the annular seat and a radial outer face of the stem ; characterised in that the liner comprises a flange , wherein a plurality of extensions extend outwardly from the flange , and wherein outlet ports are situated between adjacent extensions . a liner , the liner defining a flow passage aligned along a longitudinal axis defined by the liner , the flow passage having an inlet portion and an outlet portion downstream from the inlet portion relative to the direction of the flow of fluid through the flow passage ; a poppet , the poppet having a first flow face and a second flow face , wherein an axially extending sidewall of the poppet is interposed between the first and second flow faces ; and a biasing element operably coupled between the poppet and the liner to bias the first flow face against an annular seat defined by the liner in a closed position of the check valve ; wherein the poppet is movable from the closed position to an open position wherein the poppet is unseated from the annular seat and from the open position to a full open position, wherein in the full open position an entirety of the axially extending sidewall is downstream relative to the direction of fluid flow through the flow passage from a downstream edge of the outlet portion ; wherein a radial clearance is formed between the axially extending sidewall and the outlet portion of the flow passage such that a leakage flow is permitted from the inlet portion through the outlet portion in the open position; wherein the poppet comprises a stem leading to a head and wherein, prior to unseating, fluid pressure acts on a portion of the first flow face of the head of the poppet ; and wherein the portion of the first flow face is defined radially between a radial inner face of the annular seat and a radial outer face of the stem ; characterised in that the liner comprises a flange , wherein a plurality of extensions extend outwardly from the flange , and wherein outlet ports are situated between adjacent extensions . <EOS>