Abstract: Record storage apparatus including a pack of coaxially arranged rotating flexible disks uniformly spaced by means providing interstices through which pressure fluid is normally supplied at a preselected flow rate to maintain the disks stabilized in substantial parallelism during rotation. The pack is split at a selected axial position to cause a disk at each side of the split to spread and create a gap into which a transducer is insertable. A movable means concentrically disposed within the pack and positioned at the said selected position sealingly isolates the interstices at one side of the split from those at the opposite side. After insertion of the transducer, flow rate of pressure fluid to the disks at one side of the movable means is increased to restore the disks at said side to stabilized condition and concurrently fluid pressure load the particular disk at one side of said gap operatively against the transducer.