1/4-28 X 5/8" 六角頭螺絲 | 美國製造 | 8級鋼 黃鋅鍍層 | 全螺紋 (300個/包)

These threads cut clean and held up under a heavy clamp load without any stripping — exactly what I needed for a jig I’m building. The yellow zinc finish looks consistent across the whole batch, too.

The heads are perfectly flush in my fixture plates and the threads cut clean all the way down—no galled or skipped ones in the whole 300-count box. Yellow zinc finish hasn't shown a speck of rust after a week in a damp shop.

Finally, a bolt that doesn't strip under torque—used these on a custom jig and the hex head gave my socket a perfect bite each time. Grade 8 holds up exactly as expected.