PROTO Open End Wrench: Alloy Steel, Satin, 5/16 in_9/32 in Head Size, 3 1/2 in Overall Lg
The PROTO J3220 is an SAE double-end open end wrench made from alloy steel with a satin finish. It features 5/16 in and 9/32 in head sizes and a 3 1/2 in overall length. This standard wrench is manufactured by PROTO.
SKU 3G-OTH-284866
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Product Description
The PROTO J3220 is an SAE double-end open end wrench made from alloy steel with a satin finish. It features 5/16 in and 9/32 in head sizes and a 3 1/2 in overall length. This standard wrench is manufactured by PROTO.
Frequently Asked Questions
What is the PROTO J3220 open end wrench used for?
The PROTO J3220 is a double-end open end wrench used for tightening or loosening hex fasteners in confined spaces. It is common in automotive repair, industrial maintenance, and general mechanical work where SAE fasteners with 5/16 in and 9/32 in head sizes are encountered.
What are the specifications of the PROTO J3220 wrench?
The PROTO J3220 is an SAE double-end open end wrench made from alloy steel with a satin finish. It has head sizes of 5/16 in and 9/32 in, with an overall length of 3 1/2 in. The manufacturer part number is J3220, and it is a standard (non-ratcheting) design.
Where to buy the PROTO J3220 wrench worldwide?
3G Electric supplies the PROTO J3220 open end wrench to customers worldwide. As a global industrial equipment distributor since 1990, we handle full logistics, customs clearance, and delivery to your location. Contact us to source this PROTO wrench for your facility.
How to select the correct PROTO open end wrench size?
To select the correct PROTO open end wrench, match the wrench head size to the fastener's hex width. For the J3220, the 5/16 in and 9/32 in openings fit corresponding SAE bolts. Ensure the wrench length provides adequate torque for the application without over-tightening.
Used in
Common applications for PROTOPROTO Products
3G Electric supplies PROTO sae, double end, open end wrenches. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.















