طقم قضيب تجويف، ساق 3/8 بوصة، كربيد

Cut a clean bore on some 4140 today with the 5/16" bar and the carbide held its edge for the whole pass — the shortest bar really gets into tight spots. Heat treated shank didn't flex at all under a heavier feed.

I was skeptical about the included carbide tips holding up in heavy use, but after setting a dozen cabinet hinges, they still cut cleanly without any chipping. The heat-treated finish gives the bars a solid feel that inspires confidence.

The carbide tips on these bars cut through steel like butter, and the 3/8" shank fits my boring head perfectly. Took me a while to find a set with such fine minimum bore sizes.