The M6-N is a black coated metal nut that is used to assemble all 18 of the different connectors in the Flexpipe system. The M6-N nut was designed to assemble Flexpipe HJ joints, and it was created to do only that. (It is essential that the bolt and nut are tightened between 12-14 N.m torque).
Be sure to select the antistatic version M6-25NWZ for all the ESD connectors.
A Flexpipe Product
For technical details and images, please search for the product using the 80/20 interactive catalogue found here: https://catalogs.8020.net/80-20-Catalog-26/C/.