2" Female Normal Pipe Thread (NPT) x 2" Buttress Male Adapter. Connect 2" NPT to buttress drums, IBC, Totes with a 2" buttress opening. Please note, not all buttress openings are the same size. Dafnas adapter will fit Buttress fittings that are 2". It will not fit into containers with a Metric opening. Please make sure your opening is NOT metric.