Fasteners aren't glamorous, but they're the reason nothing on the machine comes apart under its own vibration and weight. Grade, thread pitch, plating, head geometry — every one of those specs was chosen for a reason. Substituting the wrong one is how repairs turn into recalls.
This is the genuine Nilfisk Advance OEM NUT HEX NYL LOC SS 1/4-20, part number 56002491, brand new in the box. Factory hardware, factory fit, no improvisation required.
Not sure this is the right hardware for your machine? Send us the model and serial and we'll confirm.