Feature: 1. STABLE AND RELIABLE: Ultra low frequency pulse generator adopts imported chips for more stable frequency generation and pulse width. Double layer FR 41.2T PCB board, more stable and reliable 2. INCREASED TRANSMITTING RANGE: Enhanced 28 turn transmitter coil for increased transmitting range Increase the power switch, toggle ON position to turn on the power, OFF position to turn off the power. 3. EASY TO USE: Schumann wave generator supports both TYPE C (supports forward and reverse plugging) and USB Micro power connectors, making it easy to use. 4. STATIC PROTECTION TUBE: Schumann waves resonance generator adds high power TVS static protection tube to prevent hand and air static damage to the chip. 5. PPTC SELF RESTORING FUSE: Add PPTC self restoring fuse to prevent short circuit to completely cut off the power supply to the board. After the short circuit is removed, the fuse will automatically return to normal. Specification: Item Type: Schumann Wave Generator Material: PCB Output: 7.83Hz Pulse Square Wave Interface: Type C, Micro USB. Package List: 1 x Schumann Wave Generator