The purpose of an AC power strip equipped with MOVs or Metal Oxide Varistors is to provide instantaneous and automatic protection from intense and damaging over-voltage spikes coming in on the power line.
The ceramic MOVs act as a "sacrificial" shunt across the AC line and either shorts out, blowing the unit's fuse or, in worst cases such as lightning strike or a power line faults, evaporates and become an open circuit! MOVs protect in microseconds whereas fuses or circuit breakers work much slower with catastrophic damage already done.
Both the Power-1 and Power-2 provide superior surge protect from U.S.-made MOVs. A green fault protector indicator LED means protection is active and if this LED goes out, you should unplug the strip immediately as a surge been detected.
The Radial Engineering Power-1 and 2 also have high-rejection interference filters to keep radio frequency energy such as AM broadcast or CB/Ham radio signals out of the incoming AC power line. This noise manifests as intermittent buzzing and/or mysterious "hash" that is hearable within in your audio.
Both units offer very handy "always on" utility front socket(s)—the Power-2 has a single socket while the Power-1 has three. Both models have eight rear sockets to plug in all your gear into. These sockets are rugged 3-terminal, grounded AC sockets; four of them spaced far enough apart to accommodate wall-wart power supplies.
Power-2 also has a cool slide out tray with LEDs in selectable colors and a dim control. This tray slides out from the center of the unit and will light up the entire rack below; it makes a nice shelf for my iPhone with only a short cable required to reach the built-in USB charging port! Awesome!
The Radial Power-1 sells for $109.99 and the Power-2 sells for $199 MSRP.