25L Drum/Polycan Adapter Polycan adaptor that fits male (57mm to 61mm) BSP threads : DIN61, 61mm ID buttress thread female x 2″ BSP/57mm ID female. Use on polycans with external male threads to convert to standard 2″ female NPS/BSP thread. Fits most 20 and 25 litre polycans. Commonly paired with AXASS31602, DTP03 and AVL39 for use on 20 and 25 Litre polycans with external neck threads.