be evident of course that the pattern of locator holes whether single or double pattern will be coordinated in the usual case with a particular stack in mind the stack being comprised of certain number of such disks with each disk in the stack having its own unique variation in the common pattern of locator holes e g each with a unique number or relative location of holes thus as more fully described below one may manufacture these disks in sets for efficiency and convenience sake for instance to render a pack such as shown in fig4 one may punch out a set of 34 first 34 i e d 1 disks then a set of 34 second 34 d 2 disks and so forth the disk packs being each assembled thereafter by collating one each from the d 1 d 2 d 3 etc sets up to a prescribed total number d n in the pack as a feature of convenience the disk total may be left somewhat 34 open ended 34 and variable so that disks may be added at any time after a pack is first assembled manufacturers will find it particularly convenient to manufacture flexible disks according to the invention by relatively convenient inexpensive means such as in a cutting out or stamping operation as detailed below for instance for embodiments as in fig4 a die press arrangement of the type known for working with such polymer sheets may be made up to cut the 34 d 1 34 disk pattern then it may be modified very slightly to cut the 34 d 2 34 disk pattern then modified again for the 34 d 3 34 disk pattern etc see ex 1 below alternatively in the case of the 34 double set 34 of locator holes.