Metric Hex Key Set (9 pc.) | Precise Fastening Torque | Proto J4984

Description: Solve clearance issues with the J4984. A 9-piece short-arm metric hex key set in alloy steel with black oxide finish for high-torque industrial use.

Precision Fastening in High-Clearance Environments

The Proto J4984 Metric Hex Key Set (9 pc.) is the industrial standard for accessing recessed fasteners in tight mechanical assemblies. Crafted from high-strength alloy steel and finished with a protective black oxide coating, this set delivers the exact torque needed without the risk of stripping or tool deformation.

At a Glance

• 9-Piece Range: Covers essential metric sizes from 1.5mm to 10mm for comprehensive workshop utility.
• Short-Arm Geometry: Designed specifically for low-clearance areas where standard-length keys cannot maneuver.
• Molded Organizer: Includes a heavy-duty plastic holder with size-etched labels for instant identification and inventory management.
• Professional Black Oxide Finish: Provides superior corrosion resistance and a non-slip grip in oily environments.

Ideal Use Cases

• Industrial Machinery Maintenance: Essential for tightening set screws in motor housings and gearboxes where space is extremely restricted.
• Automotive Precision Work: A must-have for modern engine bays and interior trim fasteners that require a reliable Metric Hex Key Set (9 pc.).
• Aerospace Component Assembly: Meets the rigorous ANSI B18.3.2M specifications required for safety-critical fastening tasks.

Core Performance Features

Industrial Alloy Steel Construction

The Tech: Forged from high-grade alloy steel and heat-treated for maximum hardness.

The Impact: This Metric Hex Key Set (9 pc.) resists twisting and “cam-out,” allowing you to apply high leverage to stubborn or rusted fasteners without damaging the tool.

ANSI B18.3.2M Compliance

The Tech: Precision-machined to meet strict American National Standards Institute dimensional tolerances.

The Impact: Guarantees a “snug-fit” engagement with fastener heads, reducing the likelihood of rounding out the hex socket and ensuring predictable performance in professional settings.

Trust Signals

Manufactured by Proto, a leader in industrial-grade hand tools, the Proto J4984 is built for high-mileage daily use. Its durable black oxide finish and ANSI-certified engineering provide technicians with the reliability needed for high-stakes maintenance and repair operations.

Technical Specifications

Maintenance & Care

To prevent surface oxidation over time, wipe each key with a light coat of machine oil before returning it to the molded holder. Avoid using the keys with cheater bars or impact drivers, as they are specifically designed for manual torque application.

Conversational FAQ

What are the sizes included in the 9-piece Proto metric hex key set?

The Proto J4984 set includes nine standard metric sizes: 1.5, 2, 2.5, 3, 4, 5, 6, 8, and 10 mm.

Are short-arm hex keys better for high-torque applications?

Short-arm keys like the Proto J4984 are ideal for tight spaces, but they also offer a more rigid feel with less “flex” than long-arm versions, allowing for precise torque transmission in restricted areas.

Is the Proto J4984 set corrosion resistant?

Yes, this Metric Hex Key Set (9 pc.) features a premium black oxide finish that protects the alloy steel from moisture and common workshop chemicals.

• 1.5mm x 1-47/64 (LA) x 33/64 (SA) Hex Key (J46306)
• 2mm x 1-59/64 (LA) x 5/8 (SA) Hex Key (J46308)
• 2.5mm x 2-11/64 (LA) x 45/64 (SA) Hex Key (J46310)
• 3mm x 2-7/16 (LA) x 3/4 (SA) Hex Key (J46312)
• 4mm x 2-43/64 (LA) x 15/64 (SA) Hex Key (J46314)
• 5mm x 3-5/64 (LA) x 1-1/16 (SA) Hex Key (J46316)
• 6mm x 3-15/32 (LA) x 1-7/32 (SA) Hex Key (J46318)
• 8mm x 3-55/64 (LA) x 1-3/8 (SA) Hex Key (J46320)
• 10mm x 4-19/64 (LA) x 1-17/32 (SA) Hex Key (J46322)