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Rectangular metal machine key with square ends, 3 inches long, 3/8 inch square

MIDWEST FASTENER CORP

MIDWEST FASTENER CORP 34283 lockout kit

SKU CH-KZJG-APPNV

A 3-inch square-end machine key fits 3/8-inch keyways for secure shaft-to-hub torque transmission

  • Square-end machine key fits standard keyways
  • 3-inch length suits common shaft sizes
  • 3/8-inch square cross-section matches standard slots
  • Durable steel construction resists wear under load
  • Model 34283 identifies exact replacement part

Machine key for shaft assemblies

The Midwest Fastener 34283 is a square-end machine key measuring three inches long and three-eighths inch square. It transmits torque between a shaft and a mounted component such as a gear, pulley or coupling. Maintenance technicians and machine builders use it to replace worn keys or to complete new assemblies.

Simple press-fit installation

The key fits into a matching keyway cut in both the shaft and the hub. Installation requires aligning the keyways, inserting the key and securing the assembly with a set screw or retaining ring. Problems arise when the keyway is oversized, undersized or burred, causing the key to rock or shear under load.

Verify keyway dimensions before ordering

Confirm that your shaft and hub keyways are cut to a three-eighths inch square profile and that the available keyway length accommodates a three-inch key. Check the keyway depth and corner radii to ensure full seating. This key does not suit rectangular or metric keyway profiles.

Highlights

  • Square-end machine key fits standard keyways
  • 3-inch length suits common shaft sizes
  • 3/8-inch square cross-section matches standard slots
  • Durable steel construction resists wear under load
  • Model 34283 identifies exact replacement part

Specifications

BrandMIDWEST FASTENER

Questions about this item

How do I confirm the machine key fits correctly after installation?

The square end should seat fully in the keyway with the 3 in length and 3/8 in square dimension matching the slot, allowing the hub or gear to rotate without play.

What comes in the package and do I need any extra hardware?

The box contains the MIDWEST FASTENER 34283 machine key only; no additional fasteners or tools are included.

Which version of the 34283 key should I choose for my application?

The 34283 is a single specification — 3 in long with a 3/8 in square end — so select it when those exact dimensions match your keyway requirements.

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