Verykool i605 - Manual (Page 10)

Accessories
Li-Ion battery is the manufacturer-approved rechargeable battery
available for your phone. May be some batteries perform best
after several full charge/discharge cycles.
Use batteries, chargers and accessories approved by the phone
manufacturer with this particular model. The use of any other
type will invalidate any approval or warranty applying to the
phone, and may be dangerous.
Please consult with your dealer for availability of approved
accessories.
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