PROTO Crowfoot Socket Wrench: Alloy Steel, Chrome, 3/8 in Drive Size
The PROTO J4921MCF is a metric open end crowfoot wrench made of alloy steel with a chrome finish. It features a 3/8-inch drive size and a 21 mm head size, designed for use with standard ratchets and torque wrenches.
SKU 3G-OTH-315015
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Product Description
The PROTO J4921MCF is a metric open end crowfoot wrench made of alloy steel with a chrome finish. It features a 3/8-inch drive size and a 21 mm head size, designed for use with standard ratchets and torque wrenches.
Frequently Asked Questions
What is the PROTO J4921MCF crowfoot socket wrench used for?
The PROTO J4921MCF is a metric open end crowfoot wrench used to access fasteners in tight spaces where a standard socket or wrench cannot fit. It attaches to a 3/8-inch drive ratchet or torque wrench, making it ideal for automotive, industrial, and maintenance applications requiring precise torque in confined areas.
What are the specifications of the PROTO J4921MCF crowfoot wrench?
The PROTO J4921MCF is made of alloy steel with a chrome finish. It has a 3/8-inch drive size and a 21 mm head size. This metric open end crowfoot wrench is designed for use with standard ratchets and torque wrenches, providing reliable performance in tight-access fastening tasks.
Where to buy the PROTO J4921MCF crowfoot wrench worldwide?
3G Electric supplies the PROTO J4921MCF crowfoot wrench 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 tool for your maintenance or production needs.
How to select the correct crowfoot wrench size for a fastener?
To select the correct crowfoot wrench, match the head size to the fastener's nut or bolt dimension. For the PROTO J4921MCF, the 21 mm head fits a 21 mm fastener. Ensure the drive size (3/8 inch) matches your ratchet or torque wrench. Always verify the fastener's exact size before use to avoid damage.
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Common applications for PROTOPROTO Products
3G Electric supplies PROTO metric open end crowfoot wrenches. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.















