A servo valve comprising: a fluid supply; a first stage of the servo valve; a second stage of the servo valve; and a filter assembly; wherein the filter assembly filters fluid from the fluid supply to the first stage of the servo valve; the filter assembly comprising: a first fluid nozzle defining a first fluid passage therethrough between a first fluid inlet and a first fluid outlet; a second fluid nozzle defining a second fluid passage therethrough between a second fluid inlet and a second fluid outlet; characterized by: the first and second fluid nozzles arranged in end to end abutment with each other to form a single tubular fluid nozzle unit in which the first and second fluid inlets are adjacent each other, and the first and second fluid passages align to form a common fluid passage through the tubular fluid nozzle unit, the first fluid outlet being at a first end of the tubular fluid nozzle unit and the second fluid passage being at a second, end of the tubular fluid nozzle unit; a recess formed between the first end and the second end and around the periphery of an outer surface of the tubular fluid nozzle unit in a region where the first and second fluid inlets are located; and a perforated filter member provided in the recess around the tubular fluid nozzle unit and across the first and second fluid inlets. a fluid supply; a first stage of the servo valve; a second stage of the servo valve; and a filter assembly; wherein the filter assembly filters fluid from the fluid supply to the first stage of the servo valve; the filter assembly comprising: a first fluid nozzle defining a first fluid passage therethrough between a first fluid inlet and a first fluid outlet; a second fluid nozzle defining a second fluid passage therethrough between a second fluid inlet and a second fluid outlet; characterized by: the first and second fluid nozzles arranged in end to end abutment with each other to form a single tubular fluid nozzle unit in which the first and second fluid inlets are adjacent each other, and the first and second fluid passages align to form a common fluid passage through the tubular fluid nozzle unit, the first fluid outlet being at a first end of the tubular fluid nozzle unit and the second fluid passage being at a second, end of the tubular fluid nozzle unit; a recess formed between the first end and the second end and around the periphery of an outer surface of the tubular fluid nozzle unit in a region where the first and second fluid inlets are located; and a first fluid nozzle defining a first fluid passage therethrough between a first fluid inlet and a first fluid outlet; a second fluid nozzle defining a second fluid passage therethrough between a second fluid inlet and a second fluid outlet; characterized by: the first and second fluid nozzles arranged in end to end abutment with each other to form a single tubular fluid nozzle unit in which the first and second fluid inlets are adjacent each other, and the first and second fluid passages align to form a common fluid passage through the tubular fluid nozzle unit, the first fluid outlet being at a first end of the tubular fluid nozzle unit and the second fluid passage being at a second, end of the tubular fluid nozzle unit; a recess formed between the first end and the second end and around the periphery of an outer surface of the tubular fluid nozzle unit in a region where the first and second fluid inlets are located; and the first and second fluid nozzles arranged in end to end abutment with each other to form a single tubular fluid nozzle unit in which the first and second fluid inlets are adjacent each other, and the first and second fluid passages align to form a common fluid passage through the tubular fluid nozzle unit, the first fluid outlet being at a first end of the tubular fluid nozzle unit and the second fluid passage being at a second, end of the tubular fluid nozzle unit; a recess formed between the first end and the second end and around the periphery of an outer surface of the tubular fluid nozzle unit in a region where the first and second fluid inlets are located; and a perforated filter member provided in the recess around the tubular fluid nozzle unit and across the first and second fluid inlets.