Description

SQUARE NUT DIN 557.

A square nut DIN 557 is a four-sided nut. Compared to standard hex nuts, square nuts have a greater surface in contact with the part being fastened, and therefore provide greater resistance to loosening (though also greater resistance to tightening). Square nuts are typically mated with square-headed bolts.

Square nut size refers to its nominal thread diameter. Typically, machine screw sizes range from about #2 to 1/2″ and regular from 1/4″ to 1 1/2″ & M6 TO M36.

This type of nut area four-sided nut. Compared to standard hex nuts, square nuts have a greater surface in contact with the part being fastened, and therefore provide greater resistance to loosening. They are also much less likely to become rounded-off after repeated loosening/tightening cycles.