Send a part number, a photo, or a whole BOM — we supply it and stand behind it. Worldwide shipping to 80+ countries.

PROTO Flex Socket: 3/8 in Drive Size, 5/8 in Socket Size, 12-Point, Std, Chrome - 3/8" Drive SAE Flex Sockets
PROTO3/8" Drive SAE Flex Sockets

PROTO Flex Socket: 3/8 in Drive Size, 5/8 in Socket Size, 12-Point, Std, Chrome

The PROTO Flex Socket (MPN J5277A) is a 3/8" Drive SAE Flex Socket with a 5/8" socket size and 12-point standard configuration. It features a Chrome finish and is Not Tether Capable, as specified by the manufacturer…

SKU 3G-OTH-307965

Brand
PROTO
Item
Flex Socket: 3/8 in Drive Size, 5/8 in Socket Size, 12-Point, Std, Chrome
Category
3/8" Drive SAE Flex Sockets
Available to Order
Trade pricing by quote — replies within 24h
Qty
WhatsApp an engineerMessage via Telegram
No account needed — your quote request goes straight to our engineers. A free account lets you track quotes and re-order faster.
Worldwide Shipping
Air & sea freight
Datasheet on Request
Technical specs
1-Day Quote
Replies within 24h

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
J5277A
Type
12-Point, Std, Chrome, Not Tether Capable
Socket Size
5/8 in

Technical Documents

No technical documents available for this product.
Request documentation
Not sure this is the right part? Get a recommendation.

Need installation or engineering help?

Installation, commissioning, maintenance plans, system design, and bundled product + service quotes — one team handles the full scope.
Talk to an engineer

Ask a question

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

Product Description

The PROTO Flex Socket (MPN J5277A) is a 3/8" Drive SAE Flex Socket with a 5/8" socket size and 12-point standard configuration. It features a Chrome finish and is Not Tether Capable, as specified by the manufacturer PROTO.

Frequently Asked Questions

What is the PROTO Flex Socket J5277A used for?

The PROTO Flex Socket J5277A is used for turning fasteners in tight or awkward spaces where a straight socket cannot reach. Its flex design allows the socket to pivot, providing access to bolts and nuts in confined engine compartments, machinery, and industrial equipment. It is a standard 12-point chrome socket for general maintenance and repair.

What are the specifications of the PROTO Flex Socket J5277A?

The PROTO Flex Socket J5277A has a 3/8 in drive size and a 5/8 in socket size. It features a 12-point standard configuration with a chrome finish. The socket is not tether capable, as specified by PROTO. The manufacturer part number is J5277A. It is designed for professional use in automotive and industrial applications.

Where to buy the PROTO Flex Socket J5277A worldwide?

You can source the PROTO Flex Socket J5277A through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time. 3G Electric supplies this PROTO socket to procurement teams and maintenance professionals internationally.

How to select the correct PROTO flex socket size?

To select the correct PROTO flex socket, match the drive size to your ratchet or tool (e.g., 3/8 in) and the socket size to the fastener head (e.g., 5/8 in). Confirm the point configuration (12-point for hex fasteners) and finish (chrome for corrosion resistance). For tethering requirements, note that the J5277A is not tether capable. Always verify the manufacturer part number J5277A.

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 3/8" drive sae flex sockets. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

You might also need

Burners & Combustion Pumps & Compressors Spare Parts All Products

Compatible alternatives & equivalents

Cross-referenced by specification & description
PROTO Flex Socket: 3/8 in Drive Size, 1/2 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J5275A)
PROTO
PROTO Flex Socket: 3/8 in Drive Size, 1/2 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J5275A)
PROTO Flex Socket: 3/8 in Drive Size, 3/4 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J5279A)
PROTO
PROTO Flex Socket: 3/8 in Drive Size, 3/4 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J5279A)
PROTO Flex Socket: 3/8 in Drive Size, 7/16 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J5274A)
PROTO
PROTO Flex Socket: 3/8 in Drive Size, 7/16 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J5274A)
PROTO Flex Socket: 3/8 in Drive Size, 13/16 in Socket Size, 12-Point, Std, Chrome (MPN J5280A)
PROTO
PROTO Flex Socket: 3/8 in Drive Size, 13/16 in Socket Size, 12-Point, Std, Chrome (MPN J5280A)
PROTO Flex Socket: 1/4 in Drive Size, 9/32 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J4777TA)
PROTO
PROTO Flex Socket: 1/4 in Drive Size, 9/32 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J4777TA)
PROTO Flex Socket: 1/4 in Drive Size, 3/8 in Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J4773A)
PROTO
PROTO Flex Socket: 1/4 in Drive Size, 3/8 in Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J4773A)

More from PROTO

View all PROTO parts
PROTO Flex Socket: 3/8 in Drive Size, 7/16 in Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J5274HA)
PROTO
PROTO Flex Socket: 3/8 in Drive Size, 7/16 in Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J5274HA)
PROTO Flex Socket: 3/8 in Drive Size, 3/8 in Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J5273HA)
PROTO
PROTO Flex Socket: 3/8 in Drive Size, 3/8 in Socket Size, 6-Point, Std, Chrome, Not Tether Capable (MPN J5273HA)
PROTO Flex Socket: 3/8 in Drive Size, 11/16 in Socket Size, 12-Point, Std, Chrome (MPN J5278A)
PROTO
PROTO Flex Socket: 3/8 in Drive Size, 11/16 in Socket Size, 12-Point, Std, Chrome (MPN J5278A)
PROTO Flex Socket: 3/8 in Drive Size, 9/16 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J5276A)
PROTO
PROTO Flex Socket: 3/8 in Drive Size, 9/16 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J5276A)
PROTO Flex Socket: 3/8 in Drive Size, 3/8 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J5273A)
PROTO
PROTO Flex Socket: 3/8 in Drive Size, 3/8 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J5273A)
PROTO Flex Socket: 3/8 in Drive Size, 9/16 in Socket Size, 6-Point, Deep, Chrome, Not Tether Capable (MPN J5276LHA)
PROTO
PROTO Flex Socket: 3/8 in Drive Size, 9/16 in Socket Size, 6-Point, Deep, Chrome, Not Tether Capable (MPN J5276LHA)
PROTO Flex Socket: 3/8 in Drive Size, 5/16 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J5272A)
PROTO
PROTO Flex Socket: 3/8 in Drive Size, 5/16 in Socket Size, 12-Point, Std, Chrome, Not Tether Capable (MPN J5272A)
PROTO Flex Socket: 3/8 in Drive Size, 15/16 in Socket Size, 12-Point, Std, Chrome (MPN J5282A)
PROTO
PROTO Flex Socket: 3/8 in Drive Size, 15/16 in Socket Size, 12-Point, Std, Chrome (MPN J5282A)