Duo Type II Recharger: Marketing Number Correction (11/93)
I bought a PowerBook Duo Rechargeable Battery High Capacity Type II (M1835LL/A). It came with a slip of paper advising me to use "M1812" to charge the battery. I assumed this was a new battery recharger, but it's not in the product list.
The marketing number M1812 is inaccurate. The correct number for the Type II Duo Battery Recharger is M4178LL/B (Service Part 922-0576).