They were packed in a sealed foil envelope to avoid unnecessary contamination. Each pack contains 25 electrodes.
The pads are ideal for people who find using their palm / skin for ECG measurements difficult (palms are too dry), when the signals emitted by the user are too weak or the patient cannot hold the machine steady.
They are for use with ECG machine which has 3-lead electrodes cable. For example, Heal Force Prince 180A, 180B ECG Monitors (Requires a 3-lead wire to connect to the monitor)
**Not for long term use**