How it works:
1) The wax to be melted goes in the green top/lid which is removeable (see photos).
2) The tea light goes in the larger bottom/base. There is no opening on the side of the base, so you put the tea light candle in from the top when the green top/lid is removed.
3) The bowl part of the green top/lid measures 3 inches across and a little more than 1/2 (9/16) inch deep. I am not familiar with the size of tarts, but you can determine how many tarts can be burned from these measurements.
4) There is no electric component to this item. The tart is heated from a burning tea light candle.