A tractor and a trailer with an air brake hose connection system, the air brake hose connection system comprising: a female coupling attached to a tractor; a male coupling attached to the tractor; a primary air hose (8, 38) including a male coupling (21, 41) at a tractor end thereof to connect with the female coupling attached to the tractor and with a coupling at a trailer end thereof adapted to disconnectably connect to a trailer; a secondary air hose (9, 39) including a female coupling (22,42) at a tractor end thereof to connect with the male coupling attached to the tractor and with a coupling at a trailer end thereof adapted to disconnectably connect to the trailer; the trailer end coupling of each hose (8, 9, 38, 39) including a self-sealing valve (45, 47) to ensure that the trailer end of the hose remains sealed when disconnected from the trailer; the female coupling attached to the tractor incorporating a generally cylindrical end body part and a sleeve retractable along the end body part to release the male coupling (21, 41) of the primary air hose (8, 38) from the female coupling; the female coupling (22, 42) of the secondary air hose (9, 39) incorporating a generally cylindrical end body part and a sleeve retractable along the end body part to release the secondary air hose (9, 39) from the male coupling attached to the tractor; a first lock mechanism adapted to prevent unauthorised disconnection of the primary air hose (8, 38) and located at least partly around the end body part of the female coupling attached to the tractor and preventing the sleeve from being retracted sufficiently to release the male coupling (21, 41) of the primary air hose (8, 38); and a second lock mechanism adapted to prevent unauthorised disconnection of the secondary air hose (9, 39) and located at least partly around the end body part of the female coupling (22, 42) of the secondary air hose (9, 39) and preventing the sleeve from being retracted sufficiently to release the male coupling attached to the tractor. a female coupling attached to a tractor; a male coupling attached to the tractor; a primary air hose (8, 38) including a male coupling (21, 41) at a tractor end thereof to connect with the female coupling attached to the tractor and with a coupling at a trailer end thereof adapted to disconnectably connect to a trailer; a secondary air hose (9, 39) including a female coupling (22,42) at a tractor end thereof to connect with the male coupling attached to the tractor and with a coupling at a trailer end thereof adapted to disconnectably connect to the trailer; the trailer end coupling of each hose (8, 9, 38, 39) including a self-sealing valve (45, 47) to ensure that the trailer end of the hose remains sealed when disconnected from the trailer; the female coupling attached to the tractor incorporating a generally cylindrical end body part and a sleeve retractable along the end body part to release the male coupling (21, 41) of the primary air hose (8, 38) from the female coupling; the female coupling (22, 42) of the secondary air hose (9, 39) incorporating a generally cylindrical end body part and a sleeve retractable along the end body part to release the secondary air hose (9, 39) from the male coupling attached to the tractor; a first lock mechanism adapted to prevent unauthorised disconnection of the primary air hose (8, 38) and located at least partly around the end body part of the female coupling attached to the tractor and preventing the sleeve from being retracted sufficiently to release the male coupling (21, 41) of the primary air hose (8, 38); and a second lock mechanism adapted to prevent unauthorised disconnection of the secondary air hose (9, 39) and located at least partly around the end body part of the female coupling (22, 42) of the secondary air hose (9, 39) and preventing the sleeve from being retracted sufficiently to release the male coupling attached to the tractor.