A flexible elastic container having a configuration matching an internal configuration of a standard bucket is provided. The flexible elastic container clings to the inner surface of a bucket without any bubbles or wrinkles due to a specially selected wall material. Container walls are made of a thin plastic film. A bottom surface of the container is made from a bubble wrap material with a high number of bubbles per container's bottom. The film material making the container walls is attached to a bubble wrap material of the container bottom by glue or by a thermal impulse method.