A sealing assembly for controlling a flow of fluid through a fluid line has a housing having a first end opposite a second end with a hollow interior extending therebetween and an elastically resilient plug disposed within the hollow interior of the housing. The plug has a body engagable with a seat within the housing and a tension member having a first end connected to the body and a second end connected to the housing. The tension member is pre-loaded in tension to urge the body of the plug against the seat to seal the hollow interior of the housing. The body is movable away from the seat when the plug is acted upon by a fluid pressure greater than a pre-load force of the tension member.