- R160401N52Dimension: 1/2" od x 1/8" id x 1/32"Material: Sintered Neodymium MagnetGrade: N52Coating: NiCuNi(Nickel)$0.51R160404N52Dimension: 1/2" od x 1/8" id x 1/8"Material: Sintered Neodymium MagnetGrade: N52Coating: NiCuNi(Nickel)$1.21R160804N52Dimension: 1/2" od x 1/4" id x 1/8"Material: Sintered Neodymium MagnetGrade: N52Coating: NiCuNi(Nickel)$1.21