This adapter allows for a Bondteck DDG extruder to work on an Ultimaker 2
https://www.bondtech.se/en/product/ddg-extruder/?attribute_pa_ddg=ultimaker-2-upgrade&gclid=CjwKCAiA45njBRBwEiwASnZT5x9QelaHHtyztIN9a5xHM77TRNlPMh-nu3pwi_dvzkw4kiahT6pQohoCuC0QAvD_BwE