1.1 This specification covers technically important, commercially available, magnetically hard sintered ferrite permanent magnets. 1.2 Ferrite permanent magnets have residual induction Br from 0.2 T (2000 G) up to about 0.5 T (5000 G) and intrinsic coercive field strength HcJ  from 160 kA/m (2000 Oe) up to about 400 kA/m (5000 Oe). Their specific magnetic hysteresis behavior (demagnetization curve) can be characterized using Test Method A977/A977M. 1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to customary (cgs-emu and inch-pound) units which are provided for information only and are not considered standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.