While it's all just made of plastic, but: The simplest ideas are often the most ingenious. Over time, many AA batteries have been with me accumulated (we play eg WII with 4 persons, and in the Wii FBŽs fit the AA batteries in), now I've bought the portable MP3 mixer from Hercules, there include pure C batteries (or even batteries). So: The Camelion adapter for very little money (and Free Shipping !!!!) ordered, and lo and behold: The everything works properly, rechargeable AA batteries into the adapter in, the adapter into the mixer and everything is OK. Conclusion: Total buy recommendation.