Type: High-Performance (HP) 4-Flute Bottoming Nut (lug nut seat cutter / reamer)
Size: 1/2" – 13 × 1-3/8" overall length
Thread: 1/2"-13 UNC (coarse thread) – the most common automotive lug stud size in North America
Material: High-speed steel (HSS) with black oxide finish
Cutting geometry: 4-flute, bottoming style (cuts all the way to the bottom of the hole for maximum cleaning depth)
Shank: 1/4" hex power shank (quick-change compatible, fits impact drivers and drills)