This Mugen Power High Capacity Battery is a rechargeable, replaceable Lithium-Ion battery designed to work with O2 XDA III / IIs / i-Mate PDA2K / T-Mobile MDA III / Qtek 9090 / SPV M2000 / Siemens SX66 / Audiovox XV6600 / PPC-6600 / PPC-6601.

Perfect for taking on long trips, this battery provides longer battery power to your PDAs. No battery memory effect with a lithium-ion battery - you can charge the battery whenever you like without fear of reducing its charge capacity.
http://www.bosity.com/p/10001729/O2-XDA-II...Ah/battery.html
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