Proto 1/2-Inch Drive Deep Socket 21mm 12-Point
The Proto J5321M is a 1/2-inch drive deep socket in 21mm size with a 12-point design, built for professional mechanics and industrial maintenance applications requiring extended reach on recessed or...
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Create A New AccountThe Proto 1/2-inch drive socket (Model J5421M) features a 21mm opening and a 12-point design, providing increased contact points for reliable torque transfer and reduced fastener rounding during heavy-duty professional use.
Built to work seamlessly within the Proto tool system, this socket is well-suited for automotive, industrial, and MRO applications where precision fit and durable performance are essential.