A bag for holding trash, diaper, and any item that needs to be contained. The bag can have an enclosure body and a mouth opening where the opening is lined with a foldable frame. The foldable frame can fold out to keep the mouth opening in an open configuration, and can collapse upon itself to keep the mouth opening in a closed configuration. The foldable frame can optionally have a locking notch, a finger, or both, all of which can be used to attach to some part of the enclosure body thereby keeping the neck of the bag twisted closed. The bag can optionally have attachment points such as apertures, sleeves, strips, and loops for securing to the locking notch. In some embodiments, the collar need not be foldable.