Hirschmann 733 877-001 ELST M PG9 Mounting Retaining Nut

Hirschmann-Retaining-Nuts-for-Built-In-Plugs-and-Couplings-Hirschmann-733-877-001-p-A-PG9-retaining-nut-for-mounting-built-in-plugs-and-couplings-p-Hirschmann-733-877-001-ELST-M-PG9-Mounting-Retaining-Nut

Price: 1.42 from Rapid Online Rapid Electronics Ltd.