DC plug size : 4.0mm 1.7mm ( Can compatible OMRON DC6V DC plug 4.0mm all machine unit ). Suitable for model OMRON M2 M3 M5 M6 M7 M 10HEM-741, HEM-746, HEM-780, HEM-7051. And can use for OMRON- Heat Pulse Massage HV-F314 / HV-F312 HV-F311 Charging.
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