Abstract: Endless strips, of film or the like, arranged in concentric inner and outer coils thereof (at least two, but possibly more) are provided as tightly wound coils with substantially no space between turns of a coil, but with radial space between the coils with a separate carriage element carrying the coils for independent rotation at different speeds but with a common velocity of the outermost turn of the outer coil and innermost turn of the inner coil corresponding to the velocity of a length of strip therebetween (moving through a film projector or other external usage means for the strip). The inner coil preferably rotates faster than the outer coil and is played out completely so that new inner coils are formed from time to time by infeed from the outer coil(s).