Abstract: A device is disclosed which provides an airtight seal for buckets and other containers not previously having a removable, easily resealable lid. The device consists of an adapter and a lid which is threaded into the adapter. The adapter is formed to drape over the rim of the container. A seal is located between the adapter and the rim and provides an airtight seal when compressed. The adapter is held in engagement with the container by a ridge which engages a lip on the rim of the container. The lid includes threads which engage threads in the adapter and a second seal is located between the adapter and the lid providing an airtight seal when compressed. In one embodiment, the lid drapes over the adapter and prevents the adapter from being disengaged from the bucket by preventing the adapter form deforming sufficiently to disengage from the rim.