1.     Open the battery door with the Meccano tool screwdriver.

2.     If used batteries are present, remove these batteries from the unit by pulling up one end of each battery. DO NOT remove or install batteries using sharp or metal tools.

3.     Install new batteries as shown in the polarity diagram (+/-) inside the battery compartment.

4.     Replace the battery door securely.

5.     Check your local laws and regulations for correct recycling and/or battery disposal.