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PROTO Socket: Metric, 1/2 in Drive Size, 21 mm Socket Size, 12-Point, Std, Chrome - 1/2" Drive Hand Sockets
PROTO1/2" Drive Hand Sockets

PROTO Socket: Metric, 1/2 in Drive Size, 21 mm Socket Size, 12-Point, Std, Chrome

The PROTO Socket: Metric is a 1/2" Drive Hand Socket, model J5421M, featuring a 21 mm, 12-point standard socket size in a chrome finish. This industrial-grade socket is designed for professional use in metric…

SKU 3G-OTH-317861

Brand
PROTO
Item
Socket: Metric, 1/2 in Drive Size, 21 mm Socket Size, 12-Point, Std, Chrome
Category
1/2" Drive Hand 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
J5421M
Type
12-Point, Std, Chrome, Socket
Socket Size
21 mm
Drive Size
1/2 in

Technical Documents

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

Product Description

The PROTO Socket: Metric is a 1/2" Drive Hand Socket, model J5421M, featuring a 21 mm, 12-point standard socket size in a chrome finish. This industrial-grade socket is designed for professional use in metric fastening applications.

Frequently Asked Questions

What is the PROTO J5421M socket used for?

The PROTO J5421M is a 1/2" drive, 21 mm, 12-point standard socket used for tightening or loosening metric fasteners in industrial maintenance, automotive repair, and assembly applications. Its chrome finish resists corrosion, making it suitable for professional shop environments.

What are the specifications of the PROTO J5421M socket?

The PROTO J5421M is a 12-point, standard, chrome socket with a 1/2 in drive size and a 21 mm socket size. It is designed for metric fasteners and is part of PROTO's industrial-grade hand socket line, model J5421M.

Where to buy the PROTO J5421M socket worldwide?

You can source the PROTO J5421M socket through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations, ensuring the socket reaches your facility regardless of location.

How to select the correct PROTO socket for metric fasteners?

To select the correct PROTO socket, match the drive size (1/2 in) to your ratchet or torque wrench, and choose a socket size (21 mm) that fits the fastener head. For metric fasteners, use a 12-point socket like the J5421M for better grip on hex bolts. Always verify the fastener type 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 1/2" drive hand 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
PROTO Socket: Metric, 1/2 in Drive Size, 21 mm Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J5421MH)
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PROTO Socket: Metric, 1/2 in Drive Size, 22 mm Socket Size, 12-Point, Std, Chrome, Socket (MPN J5422M)
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PROTO Socket: Metric, 1/2 in Drive Size, 14 mm Socket Size, 12-Point, Std, Chrome, Socket (MPN J5414M)
PROTO Socket: Metric, 1/2 in Drive Size, 20 mm Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J5420MH)
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PROTO Socket: Metric, 1/2 in Drive Size, 20 mm Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J5420MH)
PROTO Socket: Metric, 1/2 in Drive Size, 20 mm Socket Size, 12-Point, Std, Chrome, Socket (MPN J5420M)
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PROTO Socket: Metric, 1/2 in Drive Size, 20 mm Socket Size, 12-Point, Std, Chrome, Socket (MPN J5420M)

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