Use Rechargeable Batteries or With PCB Batteries. Other types of batteries may cause personal injury. Do NOT leave batteries charging unattended/overnight! 

NOTE: Use special caution when working with Li-ion cells, they are very sensitive to charging characteristics and may explode or burn if mishandled. Make sure the user has enough knowledge of Li-Ion rechargeable batteries in charging, discharging and assembly before use. Always charge in/on a fire-proof surface. Never leave charging batteries unattended. We are not responsible for damage if there is any modification of the batteries/chargers in any form or shape (including pack making). We are not responsible for any damage caused by misuse or mishandling of Li-Ion batteries and chargers. We only recommend using Lithium Ion rechargeable batteries with a control circuit (protection PCB) to assure safe charge, discharge, etc, use of lithium ion batteries with a protection circuit is potentially hazardous