Abstract: A system for optimising storage in an enclosed transport trailer (6), having transverse bearing beams (2) for supportin a load such as loaded pallets (12, 13) at a mid height of the trailer such that two storage levels are available. The beams have a wheel (10) at each end that runs in a horizontal track (11) attached to each side wall of the trailer, the track enclosing the wheels to prevent them from disengaging from the track. Adjacent beams can be attached togethe at variable spacings using a spacer bar (15) to suit a particular pallet or load size. The track has a junction adjacent th open end (20) of the trailer that leads up to another track (18) immediately below the roof line where the beams can b moved to an out of the way storage position (19) when not required.