A high pressure valve assembly, comprising: a housing comprising a proximal end and a distal end; a first bellows having a movable back end and a fixed front end opposite said movable back end, said fixed front end being operably coupled to a fixed fitting restrainably affixed along the interior of said housing; a second bellows having a fixed back end operably coupled to said fixed fitting, and a movable front end opposite said fixed back end; a fluid passage disposed within said fixed fitting, said fluid passage operably connecting said first bellows and said second bellows to form a sealed dual bellows chamber defined by said first bellows, said second bellows and said fluid passage, said sealed dual bellows chamber being substantially filled with an incompressible fluid, a pre-charge chamber having a first fixed end disposed at said proximal end and a second movable end opposite said first fixed end; wherein the movable back end of the first bellows is operably coupled to said second movable end of said pre-charge chamber; wherein the movable front end of said second bellows is operably connected to a shaft flange, said shaft flange being coupled by a shaft to a system poppet configured to seal an outlet in said distal end of said housing; and wherein a series of circumferential inlets is disposed adjacent said distal end of said housing, said inlets enabling a pressurized intake gas to enter said housing and flow through one or more access channels to exert a force against said shaft flange, and, in turn, said movable front end of said second bellows, characterized in that said first bellows includes a first limiting valve comprising a first biased spring and a first valve ball, the first limiting valve serving to seal said fluid passage when said first bellows reaches its preset partially-compressed state, in which the first valve ball is seated against the fixed fitting, thereby limiting the compression of said first bellows to a first pre-determined length in which said first bellows is not fully nested; and wherein said second bellows includes a second limiting valve that comprises a second biased spring and a second valve ball, the second limiting valve serving to seal said fluid passage when said second bellows reaches its preset partially-compressed state, in which the second valve ball is seated against the fixed fitting, thereby limiting the compression of said second bellows to a second pre-determined length in which said second bellows is not fully nested. a housing comprising a proximal end and a distal end; a first bellows having a movable back end and a fixed front end opposite said movable back end, said fixed front end being operably coupled to a fixed fitting restrainably affixed along the interior of said housing; a second bellows having a fixed back end operably coupled to said fixed fitting, and a movable front end opposite said fixed back end; a fluid passage disposed within said fixed fitting, said fluid passage operably connecting said first bellows and said second bellows to form a sealed dual bellows chamber defined by said first bellows, said second bellows and said fluid passage, said sealed dual bellows chamber being substantially filled with an incompressible fluid, a pre-charge chamber having a first fixed end disposed at said proximal end and a second movable end opposite said first fixed end; wherein the movable back end of the first bellows is operably coupled to said second movable end of said pre-charge chamber; wherein the movable front end of said second bellows is operably connected to a shaft flange, said shaft flange being coupled by a shaft to a system poppet configured to seal an outlet in said distal end of said housing; and wherein a series of circumferential inlets is disposed adjacent said distal end of said housing, said inlets enabling a pressurized intake gas to enter said housing and flow through one or more access channels to exert a force against said shaft flange, and, in turn, said movable front end of said second bellows, characterized in that said first bellows includes a first limiting valve comprising a first biased spring and a first valve ball, the first limiting valve serving to seal said fluid passage when said first bellows reaches its preset partially-compressed state, in which the first valve ball is seated against the fixed fitting, thereby limiting the compression of said first bellows to a first pre-determined length in which said first bellows is not fully nested; and wherein said second bellows includes a second limiting valve that comprises a second biased spring and a second valve ball, the second limiting valve serving to seal said fluid passage when said second bellows reaches its preset partially-compressed state, in which the second valve ball is seated against the fixed fitting, thereby limiting the compression of said second bellows to a second pre-determined length in which said second bellows is not fully nested.