sometimes one of hundred will be like that surface and side maybe 1-2mm tolerance or Groove . we will be so sorry for it ,but it will be aslo strong ,and not affect to use . so please understand it .it is normal .
Hcj ≥11 KOe
BHmax: 48-51 MGOe
Magnetization: Axially magnetized / Poles on Flat Ends
Max Operating Temperature: 80°C/176°F
Plating: nickel copper nickel triple layer plated
Caution: strong magnets are brittle; strong magnet could pinch your fingers badly; if you allow two magnets attract together, it may cracks and the chips could hurt your eyes
(The pull force was tested at 20 Celsius degree, on a polished iron plate with a thickness of 20 mm. The magnet was deducted vertically. A difference of up to -10% compared to the specified value is possible in exceptional cases.)