Review on 💪 Unleash Hard Steel Durability with KnKut Performance 5KK9 by Yousef Abood

I ordered a replacement kit and am returning this kit because one of the drill bits (3/8) has dark spots and streaks which I think could be caused by corrosion. . I used a penny I had on hand to pry each drill bit out of the cut out in the black foam liner. Each of the drill bits fit snugly into the foam pad, while the smaller diameter drill bits penetrate deep into the pad. The sizes are listed on the shanks of the four large drill bits along with "US" but I can't see the dimensions to read while the drill bits are in the foam padding. I didn't find any markings on the smallest drill bit, probably because its shank is too thin to mark. The dimensions of the drill are not indicated on the body, it is metal. There are tool marks on the flutes of the drills. The markings are particularly noticeable on large sizes. I don't see any problems with the working end (ie tips) of the drills. However, without using the exercises, I cannot comment on their effectiveness.