Bought the mills a few months ago, they do a very good, daily job.
They are metal mills, pepper: hardened steel, salt: stainless steel.
6 AA alkaline batteries per mill, these were included in the delivery.
Rechargeable battery I have not tried, with 6 batteries there are 9V at the motor. With rechargeable batteries it would be 7.2V, missing 1.8V, the motor would have much less power, would be a pity. It seems that the batteries live a long time.
The lamp is a gimmick. Made in China.