Metronomes; Electronic metronomes; Wearable activity trackers; Interfaces for computers, namely, electroencephalography (EEG) helmets allowing users to interface with computer hardware via brain activity; Sensors for scientific use to be worn by a human to gather human biometric data and also including EEG, EOG, EMG, ECG, EKG sold as a unit; Smart headphones; Headphones in the form of headbands; Computer hardware and computer peripherals