A surgical access assembly comprising: a cannula; a valve housing coupled to a proximal end of the cannula; and a valve assembly disposed in the valve housing, the valve assembly including: a centering mechanism including a hoop having fingers extending radially outwards from an outer surface of the hoop, each finger being flexibly connected to the outer surface and biased away from the outer surface; a ring with an outer diameter and a flange disposed at one end of the ring, the other end of the ring abutting one end of the hoop; a retainer having a first disc disposed in the ring and a second disc disposed in the hoop, the first disc attachable to the second disc irrespective of the rotational orientation of the first disc relative to the second disc; a guard including a frame and flaps (142a-f) flexibly coupled thereto, the guard partially disposed in the first disc; and a seal including petals (162a-f) flexibly coupled to a support, the seal partially disposed in the second disc, characterised in that one of the first or second discs (180, 190) includes a ridge circumscribing a central opening (188, 198) thereof and the other of the first or second discs (180, 190) includes a slot circumscribing a central opening (188, 198) thereof, the ridge adapted to fit within the slot thereby coupling the first and second discs (180, 190). a cannula; a valve housing coupled to a proximal end of the cannula; and a valve assembly disposed in the valve housing, the valve assembly including: a centering mechanism including a hoop having fingers extending radially outwards from an outer surface of the hoop, each finger being flexibly connected to the outer surface and biased away from the outer surface; a ring with an outer diameter and a flange disposed at one end of the ring, the other end of the ring abutting one end of the hoop; a retainer having a first disc disposed in the ring and a second disc disposed in the hoop, the first disc attachable to the second disc irrespective of the rotational orientation of the first disc relative to the second disc; a guard including a frame and flaps (142a-f) flexibly coupled thereto, the guard partially disposed in the first disc; and a seal including petals (162a-f) flexibly coupled to a support, the seal partially disposed in the second disc, characterised in that one of the first or second discs (180, 190) includes a ridge circumscribing a central opening (188, 198) thereof and the other of the first or second discs (180, 190) includes a slot circumscribing a central opening (188, 198) thereof, the ridge adapted to fit within the slot thereby coupling the first and second discs (180, 190). a centering mechanism including a hoop having fingers extending radially outwards from an outer surface of the hoop, each finger being flexibly connected to the outer surface and biased away from the outer surface; a ring with an outer diameter and a flange disposed at one end of the ring, the other end of the ring abutting one end of the hoop; a retainer having a first disc disposed in the ring and a second disc disposed in the hoop, the first disc attachable to the second disc irrespective of the rotational orientation of the first disc relative to the second disc; a guard including a frame and flaps (142a-f) flexibly coupled thereto, the guard partially disposed in the first disc; and a seal including petals (162a-f) flexibly coupled to a support, the seal partially disposed in the second disc, characterised in that one of the first or second discs (180, 190) includes a ridge circumscribing a central opening (188, 198) thereof and the other of the first or second discs (180, 190) includes a slot circumscribing a central opening (188, 198) thereof, the ridge adapted to fit within the slot thereby coupling the first and second discs (180, 190).