the design of the carrier 1 to provide for increased strength and durability the supplemental strut 19 has a plurality of aperatures 16 provided therein though the supplemental strut 19 is shown as horizontal it will be appreciated that such a supplemental strut 19 could also be vertical or diagonal as shown in fig6 a pair of flexible support straps 30 are provided to secure the carrier 1 to the back 28 of an automobile seat 25 support straps 30 typically include hook like members 31 at either end of the straps 30 and a means 32 of adjusting the length of each of the straps 30 one end of each strap 30 is connected to a post 26 of a headrest 27 while the other end of each strap 30 is connected to an aperture 16 of member 6 other connection schemes may be employed such as a single strap not shown which loops around the posts 26 of the headrest 27 a biasing strap 33 preferably having an elastic component is connected at the apertures 16 in member 7 and to the lower supports not shown of the seat 25 because of the elastic component of biasing strap 33 the carrier 1 is held in tension biased against the seatback 28 other schemes may be employed such as a pair of biasing straps as shown in fig7 depending upon the configuration of the seat 25 in fig4 and 6 a pair of load retention straps 35 and 36 are provided to secure the personal oxygen system 2 in place between the first and second frame 5.