21PCS Magnetic Nut Driver Set. 7PCS imperial magnetic nut drivers: 1/4", 5/16", 3/8", 11/32", 7/16", 1/2", 9/16". 3PCS quick-release extensions: 60mm, 80mm, 100mm. High Magnetic Force: Each nut driver is equipped with a robust magnet that securely locks the drill bit, providing unmatched stability during use.
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