To close the lid on this jar, you turn the lid until you feel it click tightly — then you stop. If you continue to turn, applying more pressure, it can loosen. If this happens, just turn it further until you feel it click tight again. Please keep in mind that the jars can be rattled in shipping. As with any ink, we recommend that you open the package over a sink or other easily cleaned area, just in case. When traveling with ink, we always recommend double zip-loc bagging your ink.