براغي رأس مقبس M42-4.5 × 280 مم | محرك مقبس سداسي | ملولبة جزئيًا | فئة 12.9 سبيكة فولاذ أكسيد أسود حراري

The thermal black oxide finish gives these a nice, uniform look, and the partial threading makes alignment in my fixture a lot less fiddly. They’re hefty at 280mm, but the hex socket drive feels precise, and the 12.9 alloy steel gives me confidence in the clamping load.

Installed these on a heavy-duty jig I’m welding up, and the 12.9 alloy steel holds torque without stripping. The thermal black oxide finish is a nice touch, resists oil smudges while I’m working under the press.

Put these on a milling fixture I’m building, and the 12.9 alloy steel feels rock-solid. The black oxide finish is a nice touch, no oil slick on my hands. They seated perfectly with a hex key, no wobble.