After a little research, I figured out how to rebuild a MacPortable battery pack for about 1/3 the cost of buying one on the resale market (I've seen prices between $60 and $75 per battery). Anyway, the pack is rated at 6v/5ah, and contains three, 2v/5ah Gates Cyclon "X" cells. The X cells are two sizes above the conventional D battery. Gates no longer makes these batteries, having gotten out of the battery business. Hawker Energy Products (http://www.hepi.com) now makes these cells. These are available from Battery Specialties (1-800-854-5759) for $7.24 each ($21.72 total). Opening the battery case is also easy. The pack top is ultrasonically welded to the bottom case, but if you score the top plastic in the groove where it meets the bottom case, and then bang it with a small slot-headed screwdriver and a hammer, you can open it easily. Replace the internal cells with the new ones, observing all polarity markings and ensuring that all insulating plastic and foam pieces are replaced. You can then seal it with plastic welding cement such as X7. The only problem that I can see is creating the bars that join the cells. I'll probably use 12g copper wire in stead of bus bars. Now all I need is the batteries... Rich Cini/WUGNET &lt;nospam_rcini(a)msn.com&gt; - ClubWin! Charter Member - MCP Windows 95/Windows Networking - Preserver of "classic" computers <<<< ========== reply separator ========== >>>>>