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

The PROTO Socket: Metric is a 1/2" Drive Hand Socket, model J5321M, featuring a 21 mm socket size with a 12-point deep design. It is constructed from chrome, as specified by the manufacturer PROTO.

SKU 3G-OTH-317563

Brand
PROTO
Item
Socket: Metric, 1/2 in Drive Size, 21 mm Socket Size, 12-Point, Deep, Chrome
Category
1/2" Drive Hand Sockets
Available to Order
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Local availability & support

Delivery
Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
Payment
Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

PROTO
Manufacturer Part Number
J5321M
Type
12-Point, Deep, 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 J5321M, featuring a 21 mm socket size with a 12-point deep design. It is constructed from chrome, as specified by the manufacturer PROTO.

Frequently Asked Questions

What is the PROTO J5321M socket used for?

The PROTO J5321M is a 1/2 in drive, 21 mm, 12-point deep socket designed for fastening and loosening metric hex fasteners in industrial maintenance, automotive repair, and machinery assembly. Its deep reach and chrome finish suit high-torque applications.

What are the specifications of the PROTO J5321M socket?

The PROTO J5321M is a 12-point, deep, chrome socket with a 1/2 in drive size and 21 mm socket size. It is manufactured by PROTO under part number J5321M. The chrome construction provides corrosion resistance and durability for repeated use.

Where to buy the PROTO J5321M socket worldwide?

3G Electric supplies the PROTO J5321M socket to customers worldwide. We handle full logistics, customs clearance, and delivery to your facility. Contact us for a quote and lead time; we source genuine PROTO tools for global industrial buyers.

How to select the correct PROTO socket for a 21 mm fastener?

For a 21 mm hex fastener, use a 21 mm socket like the PROTO J5321M. Ensure the drive size matches your ratchet (1/2 in). A 12-point deep socket provides better grip on rounded bolts and reaches recessed fasteners. Always verify fastener type and torque requirements.

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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Compatible alternatives & equivalents

Cross-referenced by specification & description
PROTO Socket: Metric, 1/2 in Drive Size, 20 mm Socket Size, 12-Point, Deep, Chrome, Socket (MPN J5320M)
PROTO
PROTO Socket: Metric, 1/2 in Drive Size, 20 mm Socket Size, 12-Point, Deep, Chrome, Socket (MPN J5320M)
PROTO Socket: Metric, 1/2 in Drive Size, 22 mm Socket Size, 12-Point, Deep, Chrome, Socket (MPN J5322M)
PROTO
PROTO Socket: Metric, 1/2 in Drive Size, 22 mm Socket Size, 12-Point, Deep, Chrome, Socket (MPN J5322M)
PROTO Socket: Metric, 1/2 in Drive Size, 23 mm Socket Size, 12-Point, Deep, Chrome, Socket (MPN J5323M)
PROTO
PROTO Socket: Metric, 1/2 in Drive Size, 23 mm Socket Size, 12-Point, Deep, Chrome, Socket (MPN J5323M)
PROTO Socket: Metric, 1/2 in Drive Size, 19 mm Socket Size, 12-Point, Deep, Chrome, Socket (MPN J5319M)
PROTO
PROTO Socket: Metric, 1/2 in Drive Size, 19 mm Socket Size, 12-Point, Deep, Chrome, Socket (MPN J5319M)
PROTO Socket: Metric, 1/2 in Drive Size, 31 mm Socket Size, 12-Point, Deep, Chrome, Socket (MPN J5331M)
PROTO
PROTO Socket: Metric, 1/2 in Drive Size, 31 mm Socket Size, 12-Point, Deep, Chrome, Socket (MPN J5331M)
PROTO Socket: Metric, 1/2 in Drive Size, 25 mm Socket Size, 12-Point, Deep, Chrome, Socket (MPN J5325M)
PROTO
PROTO Socket: Metric, 1/2 in Drive Size, 25 mm Socket Size, 12-Point, Deep, Chrome, Socket (MPN J5325M)

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