Review on Premium 8pcs Double Cut Solid Carbide Burr Set for Die Grinder Drill - Ideal for Metal Wood Carving, Engraving, Polishing, Drilling - 1/4 Inch Shank by James Broome

They looked identical to the slightly more expensive set from Yufutol and were advertised as 1/4 inch. But like other product reviews that look the same, it's not 1/4 inch. Leg. They measure 6mm (5.99mm to be precise) so are not attached to the collet on my Harbor Freight grinder. I went ahead and ordered a set from Yufutol and these shafts measure exactly 1/4" (6.35mm). Also, the burr parts themselves appear to be stronger/heavier than this set.