... 3)has strong magnetic force Large Ring magnet N35,N38,N40,N42,N45,N48,N50,N52(M,H,SH,UH,EH ... with hole High coercive forceNeodymium Ring Magnet with N35,N38,N40,N42,N45,N48,N50,gradeProduct specifications:1. Ring NdFeB magnet ... with different grades of: N35,N38,N40,N42,N45,N48,N50(M,H,SH,UH,EH) etc ...