This item is great. Soft butter available, always, and no hygiene issues, is very convenient. I found the descriptions I read were confusing. To use correctly, you just fill fill the bottom about 1/2 full with water, load the top with soft butter and close the two together. The top takes 1 stick of soft butter.
This item is fantastic...Butter becomes so much better to spread on bread. I found the item to be very well-made...would have liked it about 20% larger and with a mark on the inside to indicate how much water to put in the base.