ZiP Factory Engineers have diagnosed some too tight tolerances in certain early units ONLY in this production range *****AAA130 - AAA999 and AAB100 - AAB249******  

ZiP Upgrade Kit ver. 1.0.1 ****aka "Version 101 Kit" solves the sticky mags and sticky rods issue (which may have presented as failure to feed or eject) and allows ZiP to operate under a wider set of working conditions (including use of weaker ammos... which for many users are the only ones available... for the foreseeable future...) 

The Version 101 Kit is Drop-in simple and directions are already contained in the ZiP Operator Manual and Guide for following normal disassembly.

We are pleased inform all Registered Warranty users of the pending availability of the drop - in kit. We will direct ship to all registered users in the number range above. Users must register to receive kit. There is no cost for drop-in kit. For those that have purchased a ZiP .22 LR ver. 1.0 in the above number range you must Register your Warranty to receive the free kit. 

If your ZiP .22 LR ver 1.0 is NOT in this above range, your ZiP already has this "Version 101 Kit" installed. Thank you.