Is really need one Fridge Guard / TV Guard ?

What exactly does a fridge/TV guard do, and is it necessary? Will it make my fridge/TV use more or less electric power?

How does someone know that he/she needs a fridge/TV guard? And, what are the features of a good fridge/TV guard?

Low power (under-voltage) will damage refrigeration appliance’s compressor. Fridge Guard protects your appliance by disconnecting the power when it goes below unacceptable level. Additionally, there is a delay when power returns to normal. This will ensure that the appliance is not switched on-off repeatedly during fluctuations nor is it subjected to a massive voltage normally experienced when power returns after power cuts.

TV Guard Voltage Protector and protect your LED/LCD TV and home entertainment system against all power fluctuations. It provides protection against high voltage as well as against low voltage. It provides voltage protection. It has microprocessor control. Moreover, this voltage protector protects LED/LCD TV and your home entertainment system.