WARNING! A child should never use this product unless the battery compartment cover has been properly secured. Only an adult should replace batteries. Use a Phillips screwdriver to remove the screw. Slide the battery compartment open. Remove the old batteries and dispose of immediately. Install new batteries with the plus (+) sign facing up. Close the cover and secure it with the screw. Batteries must be inserted with the correct polarity. Do not mix old and new batteries. Do not mix alkaline, standard (carbon-zinc), or rechargeable (nickel-cadmium) batteries. WARNING! Do not use rechargeable batteries. Do not recharge non-rechargeable batteries. This product uses three AG-10 button cell batteries (3x 1,5V = 4,5V). Use batteries of the same or equivalent type as recommended. The supply terminals are not to be short-circuited. Batteries should be changed when sounds mix, distort, or become otherwise unintelligible. Remove exhausted batteries from the book. AG10/LR1130. Do not dispose of this book or batteries in general waste - they MUST be recycled. Please retain this information for future reference. WARNING! The battery is hazardous. Dispose of used button batteries immediately and safely. Keep new and used batteries out of reach of children. Contains coin/button battery. Hazardous if Swallowed. The battery can cause serious injuries if it is swallowed or placed inside any part of the body. If you think batteries might have been swallowed or placed inside any part of the body, seek immediate medical attention. A child should never use this product unless the battery compartment cover has been properly secured. Examine the product and make sure the screw of battery compartment is fastened tight. Do not use if compartment is not secure. Flat batteries can still be dangerous.