Think & Tinker, Ltd.
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Ultra-Precision ER Collet Nuts

  • used in applications where speeds exceed 10,000 PRM
  • balanced to G2.5 for 20,000 RPM's
  • used on collet holders and multi-spindle heads where center or shoulder distances are critical.
ER20A Nut

ER20A Hex Nut

ER20M Nut

ER20M Mini Nut


ER-20 wrench

ER20M Castle Wrench

  • Steel : SCM430
  • H.R.C. 38-42
  • Surface Roughness: Ra 1.6um
  • Deburred & free of sharp edges & corners
  • purely tangential tightening torque
  • no radial nut distortion
  • castle design for high-torque tightening
  • secure, no-slip design
Type OD Length Thread Max. Torque
ER 11 Mini Nut 16mm 12mm M13 x 0.75 14 ft/lbs. (19 N-m)
ER 16 Mini Nut 22mm 18mm M19 x 1.0 22 ft/lbs. (30 N-m)
ER 20 Hex Nut 34mm 19mm M25 x 1.5 25 ft/lbs. (34 N-m)
ER 20 Mini Nut 28mm 19.5mm M24 x 1.0 25 ft/lbs. (34 N-m)
ER 25 Mini Nut 35mm 21mm M30 x 1.0 29 ft/lbs. (39 N-m)
CAUTION: If your spindle currently has a HEX nut, it is probably has an ER-A thread. You must use an ER-A spanner!

Get $5 off shipping on Web Orders over US$50!
Item # Description Unit Price Enter Qty.
ERPG-ER11M-NUT  ER-11 High Speed Collet mini-nut, M13 x 0.75 ER-11   $19.95 
ERPG-ER11M-SPN  ER-11M Castle wrench (for ER-11M Collet mini-nut, and tool-holder)   $14.00 
ERPG-ER16M-NUT  ER-16 High Speed Collet mini-nut, M19 x 1.0   $19.95 
ERPG-ER16M-SPN  ER-16M Castle wrench (for ER-16M Collet mini-nut, tool-holder and collet adapter)   $14.00 
ERPG-ER20A-NUT  ER-20A High Speed Collet hex nut, M25 X 1.5   $19.95 
ERPG-ER20A-SPN  ER-20A Hex wrench (for ER-20A Collet nut)   $14.00 
ERPG-ER20M-NUT  ER-20 High Speed Collet mini-nut, M24 X 1.0   $19.95 
ERPG-ER20M-SPN  ER-20M Castle wrench (for ER-20M Collet mini-nut)   $14.00 
ERPG-ER25M-NUT  ER-25 High Speed Collet mini-nut, M30 X 1.0   $19.95 
ERPG-ER25M-SPN  ER-25M Castle wrench (for ER-25 Collet mini-nut)   $14.00 
ERPG-ER32E-SPN  ER-32E Hand wrench (slotted for ER-32B collet nut)   $20.00 
Enter the desired quantity (Enter Qty) then click on the "Add to Cart" Button.



Open Monday - Friday, 08:30 to 16:30 Mountain Time.

Most orders received before noon ship within one business day,
subject to credit approval and item availability.
Orders with different billing and shipping
addresses may be delayed for address verification.