3Com Access Builder 7000 User Manual page 15

Additional Safety Information 5
This unit contains a lithium battery which is attached to a microchip on
the printed circuit board. The defective battery must be disposed of
safely in-line with the manufacturers instructions.
Interconnecting directly, or by way of other apparatus, to ports
complying with SELV requirements may produce hazardous conditions
on the network. Advice should be sought from a competent engineer
before such a connection is made.