Technical Information – Nuts and Sealing Disks


Look for the marking first.
Hook the collet into the eccentric ring of the nut first at marked point.
After hook in tilt the collet into opposite direction until the collet locks in place.
Put the locked collet together with the nut on the holder and screw it down. If possible use a torque Wrench.


Unscrew the nut from the holder.
Push the collet into the opposite direction of the marked point until the collet locks out.


If the collet is incorrectly assembled it will effect runout accuracy.
Assembling of an unlocked nut on the holder could damage it.

Recommended tightening torque:

Nut Collet Ø (mm) Torque (Nm)
UM/ER ER16 1 8
UM/ER ER16 1.5-3.5 20
UM/ER ER16 4-4.5 35
UM/ER ER16 5-10 55
UM/ER ER20 1 16
UM/ER ER20 1.5-6.5 40
UM/ER ER20 7-13 70
UM/ER ER25 1-3.5 24
UM/ER ER25 4-4.5 55
UM/ER ER25 5-17 90
UM/ER ER32 2-2.5 24
UM/ER ER32 3-22 130
UM/ER ER40 3-26 200
ER..M ER08 -5 7-8
ER..M ER11 -7 8-18
ER..M ER16 -10 8-28
ER..M ER20 -13 16-35
ER..M ER25 -17 24-40

See the Torque Wrench Product Page to view our available wrenches.

Complete Requests