Re: plug for HP33E style chargers
Probably they only come with charger itself, but since it's so easy to change the cells, it might be simpler to just charge batteries in a separate charger, and swap them as necessary (of course, this doesn't give you "unlimited" continuous use, but it serves me well enough).
I get extra NiCd cells (with "flat tops") by taking apart "cordless phone" battery packs, which happen to be made of bunches of them (Radio Shack, in USA, also has "replace-a-cell").
Alkaline batteries (of higher charge capacity) are also available (but never use them with AC charger); the slight problem of cells with "buttons" being slightly too long to insert without flattening the battery contact springs can be overcome by judicious application of a small hammer to each cell :)
As ghastly as this sounds, it's how I make batt. packs to preserve memory (and keep calcs ready to display) even in long-term storage (where NiCd's would discharge).
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