Hello. You'll need 8 small 1.5 V (AAA) batteries, or batteries if you're not very environmentally conscious. By the way, you'll need a bit of patience to "adjust the mill" (with the little knob at the bottom), but once the mechanism is set it works very well. Enjoy your purchase.
At the bottom, where the pepper comes out, there is a wheel. Turning it clockwise == finer. Anti-clockwise == coarser. The salt mill has no such wheel.
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.