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PROTO Socket Bit: 3/8 in Drive Size, Hex Tip, 4 mm Tip Size, 2 3/4 in Overall Lg - Hex Bit Sockets
PROTOHex Bit Sockets

PROTO Socket Bit: 3/8 in Drive Size, Hex Tip, 4 mm Tip Size, 2 3/4 in Overall Lg

The PROTO Socket Bit (SKU 3G-OTH-305532, MPN J4990R-4M) 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 2 3/4 in. This…

SKU 3G-OTH-305532

Also listed as: J4990R4M · J4990R 4M

Brand
PROTO
Item
Socket Bit: 3/8 in Drive Size, Hex Tip, 4 mm Tip Size, 2 3/4 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
J4990R-4M
Type
Hex Tip, Fixed Insert
Overall Lg
2 3/4 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 (SKU 3G-OTH-305532, MPN J4990R-4M) 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 2 3/4 in. This PROTO-branded tool is a hex bit socket for industrial applications.

Frequently Asked Questions

What is the PROTO J4990R-4M hex bit socket used for?

The PROTO J4990R-4M hex bit socket is used for driving hex fasteners in industrial assembly, maintenance, and repair tasks. Its 4 mm hex tip and 3/8 in drive size make it suitable for precision work on machinery, automotive components, and equipment where a fixed insert design provides secure engagement.

What are the specifications of the PROTO J4990R-4M socket bit?

The PROTO J4990R-4M socket bit has a 3/8 in drive size, a 4 mm hex tip size, and an overall length of 2 3/4 in. It features a fixed insert design and is a hex bit socket. The manufacturer part number is J4990R-4M, and it is a PROTO-branded tool for industrial applications.

Where to buy the PROTO J4990R-4M hex bit socket worldwide?

You can source the PROTO J4990R-4M hex bit socket worldwide through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time; we supply PROTO tools to industrial buyers internationally.

How to select the correct PROTO hex bit socket for my application?

To select the correct PROTO hex bit socket, match the drive size (e.g., 3/8 in) to your ratchet or driver, and the tip size (e.g., 4 mm) to the fastener. Consider the overall length (e.g., 2 3/4 in) for access. The fixed insert design of the J4990R-4M provides a secure fit for hex fasteners in industrial settings.

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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Cross-referenced by specification & description
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PROTO Socket: Metric, 3/8 in Drive Size, 14 mm Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J5214MH)
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PROTO Socket: Metric, 1/4 in Drive Size, 11 mm Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J4711M)
PROTO Socket: Metric, 3/8 in Drive Size, 14 mm Socket Size, 6-Point, Deep, Chrome, Socket (MPN J5014MH)
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PROTO Socket: Metric, 3/8 in Drive Size, 14 mm Socket Size, 6-Point, Deep, Chrome, Socket (MPN J5014MH)
PROTO Socket: Metric, 3/8 in Drive Size, 7 mm Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J5207MH)
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PROTO Socket: Metric, 3/8 in Drive Size, 7 mm Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J5207MH)

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