1)Wind generator magnet specification: Grades: N30, N33, N35, N38, N40, N42, N45, N48, N50, N52, (M, H, SH, EH, UH ) Coatings: Ni, Ni-Cu-Ni, Zn, white-blue Zn, Expoy, Gold, Parylene, Ni-Cu-Sn. Sizes: According to your requirments. Shapes: Disc, cylinder, sphere, block, ring, tile, arc, and ect. Tolerance: +/-0.05mm for small dimensions, +/-0.1mm for common specifications, +/-0.15mm for big blocks ...