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SKT 3/8DR 4MM HEX BIT - Stanley Proto Industrial Tools

Part #: J4990-4M

The Stanley Proto J4990-4M SKT 3/8DR 4MM HEX BIT is a professional-grade tool engineered for precision and durability in demanding automotive and industrial environments. Designed for mechanics and technicians, this hex bit socket provides reliable engagement with 4mm hex fasteners, ensuring efficient and secure operations on a wide range of equipment and vehicles. Its robust construction reflects Stanley Proto's commitment to quality and long-lasting performance in the workshop.

Key Features

  • Professional Grade Construction: Manufactured by Stanley Proto Industrial Tools, ensuring a high standard of quality and reliability for rigorous daily use.
  • Precision 4mm Hex Bit: Features a precisely machined 4mm hex bit for optimal fastener engagement, reducing the risk of stripping and improving torque transfer.
  • 3/8-inch Drive: Compatible with standard 3/8" drive ratchets, extensions, and torque wrenches, integrating seamlessly into existing professional tool sets.
  • Enhanced Durability: Built from high-strength materials to withstand the repetitive stresses of professional automotive and industrial applications, extending tool life.
  • Corrosion Resistant Finish: Designed to resist rust and corrosion, maintaining tool integrity and appearance even in challenging working conditions.

Applications

This 3/8" drive 4mm hex bit socket is an essential tool for various professional applications. It is ideal for automotive technicians working on vehicle components that utilize 4mm hex fasteners, such as certain engine sensors, brake caliper bolts, interior trim, and accessory mounting points. In industrial settings, it proves invaluable for the assembly, maintenance, and repair of machinery, control panels, and equipment where precise torque application to hex fasteners is critical. Its robust design makes it suitable for heavy-duty use across diverse mechanical tasks.

Only 1 left in stock - order soon

$14.65

Free shipping on orders over $250
Lower 48 states and DC. Excludes freight and oversize items.
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This product was added to our catalog on Saturday 11 July, 2026.

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