Difference between JVC GY-HD110 and JVC GY-HD110U?

the "U" stands for products designed to be sold in North American (United States and Canada). the same model for Europe would have an "E" suffix. The batteries are the same, but the chargers are slightly different (220/50 Hz vs 120/60 Hz). Look on the FCC dataplate to get the full model number for your camera.