Question : No need to add oil? Only water is enough?
Answer : YES
Question : Is it made in india?
Answer : YES . PROUDLY MADE IN INDIA
Question : is this Indian product? how long the battery will last in each diya?
Answer : MIN 48 HRS
Question : How long will it glow? My guess is it has a battery inside!! So can we change the batter?
Answer : Lasts for 100hrs approximately (as per our testing). You can change the battery, when needed.