Features：
1.Key part is imported from Japan.
2.The magnetic ball is extraordinary round and processed by a special technique.
3.The tension arm that connected with magnetic ball is made of nonmagnetic material with proper length. 4.Max test magnetic force is 49N.
5.Corresponding list of magnetic force and magnetic strength is available in the instruction of tester.
6.Magnetic strength is visual and not influenced by ways of operation which is different from Gauss meter.