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PROTO Socket Bit: 3/8 in Drive Size, Hex Tip, 4 mm Tip Size, 6 3/32 in Overall Lg - Hex Bit Sockets
PROTOHex Bit Sockets

PROTO Socket Bit: 3/8 in Drive Size, Hex Tip, 4 mm Tip Size, 6 3/32 in Overall Lg

The PROTO Socket Bit (MPN J4990-4MXL) is a hex bit socket with a 3/8 in drive size and a 4 mm hex tip size. It features a fixed insert design and has an overall length of 6 3/32 in. This PROTO-branded tool is…

SKU 3G-OTH-305234

Also listed as: J49904MXL · J4990 4MXL

Brand
PROTO
Item
Socket Bit: 3/8 in Drive Size, Hex Tip, 4 mm Tip Size, 6 3/32 in Overall Lg
Category
Hex Bit Sockets
Available to Order
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

PROTO
Manufacturer Part Number
J4990-4MXL
Type
Hex Tip, Fixed Insert
Overall Lg
6 3/32 in
Tip Size
4 mm

Technical Documents

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PROTO Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The PROTO Socket Bit (MPN J4990-4MXL) is a hex bit socket with a 3/8 in drive size and a 4 mm hex tip size. It features a fixed insert design and has an overall length of 6 3/32 in. This PROTO-branded tool is suitable for industrial fastening applications.

Frequently Asked Questions

What is the PROTO J4990-4MXL socket bit used for?

The PROTO J4990-4MXL is a hex bit socket used for industrial fastening applications. It drives hex-head fasteners with a 4 mm tip size, using a 3/8 in drive ratchet or torque wrench. Its fixed insert design provides secure engagement for assembly, maintenance, and repair tasks in manufacturing and mechanical settings.

What are the specifications of the PROTO J4990-4MXL socket bit?

The PROTO J4990-4MXL is a hex bit socket with a 3/8 in drive size and a 4 mm hex tip size. It has a fixed insert design and an overall length of 6 3/32 in. The manufacturer part number is J4990-4MXL, and it is branded by PROTO. These specs suit standard industrial fastening tools.

Where to buy the PROTO J4990-4MXL socket bit worldwide?

3G Electric supplies the PROTO J4990-4MXL socket bit worldwide. As a global industrial equipment distributor since 1990, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time. We source and deliver this PROTO hex bit socket to support your operations.

How to select the correct PROTO socket bit size?

To select the correct PROTO socket bit, match the drive size to your ratchet or wrench (3/8 in for the J4990-4MXL) and the tip size to the fastener hex recess (4 mm). Ensure the overall length (6 3/32 in) provides adequate reach. Always verify the fastener type and torque requirements before use.

Used in

Common applications for PROTO
Automotive assembly — PROTO J72102 impact socket set for fastening lug nuts on production lines
Heavy equipment maintenance — PROTO J3772T flare nut wrench for hydraulic line fittings on excavators
General industrial repair — PROTO J795SA adjustable wrench set for tightening bolts on conveyor systems
Aerospace manufacturing — PROTO J5240A slotted bit socket for adjusting fasteners in confined spaces
Oil and gas pipeline work — PROTO J5438 12-point socket for valve assembly in refineries
Construction site toolkits — PROTO J8179-T500 double box wrench for structural steel bolting

PROTO Products

3G Electric supplies PROTO hex bit sockets. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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