Specification:

Size: Ring 25.4-12.5x3 N35
Outer Dia: 25.4 mm
Inner Dia: 12.5 mm
Thickness: 3 mm 
Grade: N35
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.