Spreading cold butter can be such a drag... literally.
A butter keeper (keeps) butter perfectly soft (in summer months, even in winter) for smooth spreading all the time.
The bell-shaped top fits 1 stick of butter perfectly. The bottom well needs about 1/2-inch cool water to give you a nice inverted seal.
Simply and routinely refresh with water every 2-4 days, your butter will keep FRESH and SPREADABLE, for up to 30 days, sitting there on the counter top!