This is a large ring ferrite magnet, hard permanent magnet, the performance of the magnet is Y30BH, the size of the outer diameter is 180mm, the inner diameter has a number of sizes, such as 80mm, 85mm, 87mm, 89mm, thickness of 20mm...
This is an annular ferrite magnet with an outer diameter of 80mm, an inner diameter of 40mm, a height of 10mm, a height of 12mm, and a height of 15mm. It is anisotropy, It can be used for speakers, loudspeakers, car stereos, industrial, mechanical equipment, etc....