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PROTO Socket: Metric, 3/8 in Drive Size, 21 mm Socket Size, 12-Point, Deep, Chrome - Tether-Ready Hand Sockets
PROTOTether-Ready Hand Sockets

PROTO Socket: Metric, 3/8 in Drive Size, 21 mm Socket Size, 12-Point, Deep, Chrome

The PROTO Socket: Metric (SKU 3G-OTH-328614, MPN J5221M-TT) is a tether-ready hand socket with a 3/8 in drive size and 21 mm socket size. It features a 12-point, deep design in chrome finish, manufactured by PROTO.

SKU 3G-OTH-328614

Also listed as: J5221MTT · J5221M TT

Brand
PROTO
Item
Socket: Metric, 3/8 in Drive Size, 21 mm Socket Size, 12-Point, Deep, Chrome
Category
Tether-Ready 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
J5221M-TT
Type
12-Point, Deep, Chrome, Tether Ready
Socket Size
21 mm
Drive Size
3/8 in

Technical Documents

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

Product Description

The PROTO Socket: Metric (SKU 3G-OTH-328614, MPN J5221M-TT) is a tether-ready hand socket with a 3/8 in drive size and 21 mm socket size. It features a 12-point, deep design in chrome finish, manufactured by PROTO.

Frequently Asked Questions

What is the PROTO J5221M-TT socket used for?

The PROTO J5221M-TT is a tether-ready hand socket used for tightening or loosening metric fasteners. Its 21 mm, 12-point, deep design suits automotive, industrial, and maintenance applications where tool retention is critical. The chrome finish resists corrosion.

What are the specifications of the PROTO J5221M-TT socket?

The PROTO J5221M-TT socket has a 3/8 in drive size and a 21 mm socket size. It features a 12-point, deep profile with a chrome finish. The tether-ready design allows attachment of a lanyard for tool security. PROTO manufactures this model under MPN J5221M-TT.

Where to buy the PROTO J5221M-TT socket worldwide?

You can source the PROTO J5221M-TT socket worldwide through 3G Electric. As a global industrial equipment distributor, 3G Electric handles full logistics, customs clearance, and delivery to your location. Contact 3G Electric for availability and lead time.

How to select the correct PROTO socket size?

To select the correct PROTO socket, match the drive size (3/8 in) to your ratchet or torque wrench. The socket size (21 mm) must fit the fastener head. For deep fasteners or recessed nuts, choose a deep socket like the J5221M-TT. Tether-ready models add tool security.

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 tether-ready 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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