Internal Thread NdFeB Pot Magnet 1.Dimensions: Dia from 16 mm to 75 mm 2.Materials: NdFeB,Grade N35 to N52 (M,H,SH,UH,EH AH) 3.Plating/Coating: Zinc,Nickel,Epoxy or Color paint. 4.Magnetization direction: Axial magnetized 5.Max operating temp.: 80 to 220 degrees celsius They are suitable for strong and quickly removable fasten no need drilling.They widely use for trade fair,any shop build or other purpose.No matter use in private household or commercial or hobby applications are all suitable.