Surge protectors.

Features and benefits

• Replaceable cartridges to simplify maintenance
• Removable modules allow quick replacement without the need to disconnect wiring
• Visual indication when overloaded and replacement required
• Fast and easy installation
• Provides overvoltage protection
• Auxiliary contact options for remote monitoring.
• Mains filter options to slow down overvoltage and prevent nuisance spikes.
• 970RM/3 is an all in one solution for unifying both indirect lighting protection and overvoltage into one unit.

Reference:

https://www.clipsal.com/Trade/Products/Switchboards-Circuit-Protection/Residential/Overvoltage-Protection#.U7IRqGeKCpo