We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Cylindrical steel spring collet, silver finish, slotted sides

Sunkoo ER25 3/16" Spring Collet 26mm OD 34mm H Machine Shop Hardware

SKU CH-GD9J-0T5P4

ER25 spring collet clamps 3/16" shanks with 0.008mm accuracy using hardened 65Mn spring steel at HRC84 hardness

  • MaterialSteel
  • Selling UnitCount, 1
  • Item Count1 Count
  • FeaturesMilling Machine, Lathe, Drilling Machine
  • Precision clamping at 0.008mm accuracy for superior machining results
  • 65Mn spring steel hardened to HRC84 delivers long-term wear resistance
  • 26mm OD and 34mm height fit standard ER25 spindle systems
  • 3/16" bore secures small-diameter tools in CNC milling and engraving
  • Corrosion-resistant construction maintains performance in demanding workshop environments

ER25 Spring Collet 3/16

This ER25 spring collet is manufactured from 65Mn spring steel hardened to HRC84 for wear and corrosion resistance. It accepts a 3/16" shank and fits ER25 collet chucks used on CNC routers, milling machines, engraving equipment and lathes. The single-unit package supplies one collet ready for precision tool holding in metal, wood or plastic machining.

Sustained Load Performance

The heat-treated 65Mn spring steel construction maintains consistent clamping pressure during extended high-speed operations without deformation. Hardness of HRC84 provides the elasticity needed for repeated clamping cycles in continuous production workflows. This durability supports stable tool holding throughout long machining sessions on aluminium, steel or plastic workpieces.

ER25 Interface Limits

The collet's 1.02" (26mm) outer diameter and 1.34" (34mm) total height define the ER25 form factor it must match. Concentricity accuracy of 0.008mm (0.0032") sets the practical runout limit for the ER25 interface. Buyers needing larger shank diameters or different collet series such as ER32 or ER20 cannot use this specific 3/16" ER25 model.

Highlights

  • Precision clamping at 0.008mm accuracy for superior machining results
  • 65Mn spring steel hardened to HRC84 delivers long-term wear resistance
  • 26mm OD and 34mm height fit standard ER25 spindle systems
  • 3/16" bore secures small-diameter tools in CNC milling and engraving
  • Corrosion-resistant construction maintains performance in demanding workshop environments

Specifications

BrandSunkoo
ModelER25 3/16"
MaterialSteel
Selling UnitCount, 1
Item Count1 Count
FeaturesMilling Machine, Lathe, Drilling Machine

Questions about this item

Does the ER25 collet generate heat or vibration during continuous CNC milling?

The 65Mn spring steel hardened to HRC84 maintains clamping force without deformation, minimising runout to 0.008 mm and keeping vibration low during extended high-speed runs.

What spindle or chuck must I already have to use this 3/16" ER25 collet?

You need an ER25 collet chuck or spindle taper that accepts 26 mm outer diameter and 34 mm overall height; the collet itself is the only component supplied.

Will this 3/16" ER25 collet work in my older ER20 or ER32 tool holders?

No — the 26 mm outer diameter and 34 mm height match only ER25 holders; ER20 and ER32 pockets have different dimensions and will not accept this collet.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.