Varnishes, paints, enamels often Packed in tin cans with a wide lid-stopper. But no matter how tight it fit, the tightness over time is broken: part of the contents when pouring over the edge dries up on the edge and prevents tight closing of the jar. However, when the expenditure of material in small portions is better to pour it not so, and through the drilled a hole in the lid Ø 6 — 10 mm (depending on viscosity). The air hole Ø 3 mm do the opposite of the cover. “Plug” these holes will serve as a piece of adhesive tape or thick tape.