Mini Nuts
Compact tool holders like HSK32E and ISO20 don’t have room for a standard-profile collet nut, which is why HS Spindles carries a dedicated line of mini nuts in ER11, ER16, ER20, and ER25, plus a slotted ER40 mini nut for larger-diameter tooling in tight-clearance setups. Mini nuts use a shorter, narrower body than standard collet nuts, so they need a matching mini-nut wrench rather than a standard castle or E-style spanner – using the wrong wrench on a mini nut will round the flats without fully seating the collet. If you’re running a small-taper machine or a compact spindle where clearance is the limiting factor, these nuts let you keep full ER clamping range without the added bulk of a standard nut. Pair with the correct mini-nut wrench from our Wrenches category to get full torque without slipping.
