All headphones of the HD 200 series are working with the same electrodynamic transducer technology. Variants of the model series: Variant HD 201 HD 201 OEM HD 201S HD 202 HD 203 HD 205 Variant HD 212 PRO HD 215 HD 218 HD 219 HD 220 Variant Variant HD 228 BLACK HD 228 WHITE HD 229 HD 280 -13 HD 280 PRO HD 280 SILVER HD 238 HD 239 HD 200 PRO HD 206 HD 215 OEM HD 265-1 Applied directives and standards: The device(s): which are listed above comply with the following: Pos.-No.