05mm) Length 1' (25 40mm) Max Working Temp 80°C Plating/Coating Nickel Grade N42 This product measures 3/4' in diameter and 1' in thickness and is made of a grade N42 neodymium, iron, and boron magnetic alloy blend This magnetic blend is patent licensed and made under the ISO 9001 quality systems They are plated in a nickel-copper-nickel coating for a shiny corrosion-resistant finish The North and South poles are on the flat sides