Ear-held fixed-line handsets couple magnetically to hearing aids to ETSI ES 200 381-1 and show the T symbol of ETSI ETS 300 381, and ear-held wireless devices couple to ETSI ES 200 381-2, with TIA-1083-A and ANSI/IEEE C63.19 accepted respectively.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.