Specification:

Size: Ring  11.23-4.87x8-30H Ni
Outer Dia: 11.23 mm
Inner Dia: 4.87 mm
Thickness: 8 mm 
Grade: 30H Ni
Coating: Nickle - Ni  
Max Operating Temperature: 80°C   

Description:
Nickel Coated Magnets have many industrial, educational and household uses. These Magnets are highly resistant against demagnetization.