The most obvious change in the redesign was the removal of the ZIF cartridge-loading system that caused trouble in maintenance and game-swapping when using the NES-001 model. In that system, the user had to first open the lid of the case, slide in the cartridge, then press it down. The large space inside allowed plenty of room for dust to settle and the contact heads were almost impossible to access and clean without unscrewing the case or using the official cleaning kit. Wear and tear was another problem; with continued use, the precision of the mechanism deteriorated and the user would have to poke and nudge at the cartridge to move it to a position that would be read correctly. The NES-101 returned to the standard top-loading method, used by almost all cartridge systems before and since for its ease and reliability.
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The 10NES authentication chip was completely removed from the system in an effort to eliminate the blinking red power light problem associated with it in the NES-001 model control deck. The removal of the 10NES chip also allows the system to play games that are unlicensed and/or from different regions such as Europe, something an unmodified NES-001 model control deck cannot do.