Conventional Lead Opposed to Novel ECG (CLONE)

To blindly assess, beat-by-beat, standard ECG intervals (QRS intervals, PQ intervals, and P wave durations) of paired standard lead v4 with paired HeartWatch signals over 20 to 30 seconds of noise-free data.

Inclusion Criteria: * At least 22 years of age at time of the conventional ECG recording * Willing to participate in the study * Able to follow the protocol Exclusion Criteria * Known allergy to the electrodes used for a conventional ECG * Known allergy to any component of the HeartWatch * Known allergy to any component of the Kardia system * Inability to wear the HeartWatch on the left arm due to pre-existing medical condition (e.g., functional AV fistula in left arm, prior carcinoma with lymph node dissection or lymphedema, known blood clot or recurrent blood clots in left arm, chronic neuropathic pain in left arm, …) * Dextrocardia * Implanted functional Pacemaker of Defibrillator * Left upper arm circumference \< 22 cm or \> 45 cm