exposed point as shown in fig1 letter a corresponds to the retracted position b 1 and b 2 to different writing positions and c to maximum or fully extended position this iterative inertia telescopic pen permits special applications such as for stencils fig1 shows the feasibility of providing the bipolar inertia pen with a conventional push button without affecting its inertia bipolarity the cylinder column 78 ensures connection between a push button 79 and opposite polar slide 80 slots or windows 81 of the column 78 correspond to protuberances on the removable part 82 internal to the pen polar body groove 83 is a detent type connector between the telescoping parts polar points may be exposed or retracted simultaneously however the pen must be operated in such a way that the inertia point on the button pole is exposed after the other point and that the push button be used when the inertia point is retracted this operating procedure differs from the normal one i e in which polar points may be exposed or hidden simultaneously if necessary fig1 also shows other components previously described such as spring rest 84 sliding point 85 return spring 86 polar fixed slopes 87 polar slide slopes 88 rear dents 89 and slopes 90 fig1 shows a thin multiple point 91 for which a special binary inertia mechanism is not required fig1 shows an inertia pen comprising a multiple point 92 exceeding the carrying tube diameter 93 and normal guiding polar hole diameter the sliding refill is not free to rotate during its course due to guides 94 and 95 which receive wings 96 the main slide 97 turns in.