Samsung Washing Machine Check Nut – Pulsator/Tub Shaft Lock Nut, 54mm | "Open Lock" Type | Top Load Fully Automatic

Heavy hex check nut stamped "54" and "OPEN LOCK", used to secure the pulsator or clutch onto the tub shaft in Samsung top-load washers — the part to replace when the pulsator wobbles, clunks during spin, or won't stay seated on the shaft.