Value Collection 204-4024 ER40 Collet 3/8 Inch

Product Description

The VALUE COLLECTION 204-4024 is an ER40 series collet machined to accept a 0.375 inch (3/8 inch) shank tool. It delivers a Total Indicator Runout (TIR) of 0.0005 inches, providing the precision required for milling, drilling, and reaming operations on CNC machining centers and manual mills. ER collets of this series are workholding consumables installed by machinists and toolroom technicians. The ER40 designation reflects the collet's outer taper diameter class, which governs compatibility with matching ER40 chucks and toolholders. This collet ships individually and is suited for both production and toolroom environments where repeatable tool concentricity is essential.

The 204-4024 is used in ER40-compatible chuck bodies mounted to vertical and horizontal machining centers, CNC mills, lathes with live tooling, and manual milling machines. It is a standard choice wherever a 3/8 inch cutting tool or drill shank must be held with minimal runout. This collet is appropriate for both light-duty finishing passes and general-purpose material removal across ferrous and non-ferrous workpieces.

Key Features

• ER40 collet series — fits any ER40-standard chuck body or toolholder
• 0.375 inch (3/8 inch) bore diameter for direct tool shank acceptance
• 0.0005 inch TIR for precise tool concentricity and reduced vibration
• Single-piece construction standard to ER collet industry geometry
• UNSPSC Code 27112800 — classified under cutting and holding tools

Compatibility

Designed for use with ER40-standard collet chucks and toolholders. Compatible with any ER40 chuck conforming to the standard ER collet taper geometry and accepting a 0.375 inch bore collet.

Installation Notes

ER collets are installed and removed by machinists using an ER40 collet nut and the appropriate spanner wrench for the chuck size. Before changing collets, power down the spindle and confirm the machine is in a safe, locked-out state per your facility lockout/tagout procedure. Seat the collet fully into the collet nut before threading the assembly onto the chuck body — inserting the collet directly into the chuck without pre-seating it in the nut can damage the collet taper. Inspect the collet bore and taper seating surface for chips or wear before each use to maintain TIR performance.