A mechanical mod is an unregulated type of device. There is no circuitry in the mod to keep the voltage steady throughout the life of the battery. Since you are running directly off the battery you can't increase or decrease the voltage and the vape will slowly become weaker over the lifespan of the battery.
The use of mechanical mods is limited to advanced users with knowledge of rebuilding, safety precautions, and how to properly use and care for batteries. By purchasing this item, you agree that Steam Island LTD is not to be held liable for any damages or injuries that may occur from use or misuse of any product in this section for hardware.