Check the listing for details. iFi AC power filter. Condition: New. Listed at 109.00 USD. Product highlightsplug-in power conditioner that cleans up dirty power and diagnoses wiring/grounding issues filters out line noise to improve sound quality connect to the same wall AC outlet or power protection device that powers your audio gear works in parallel with your gear, does not connect in-line or directly to your gear over 40dB of total line noise reduction EMI/RFI noise filtering for clean power military-grade active noise cancellation addresses differential-mode and common-mode noise LED display lets you easily monitor plurality and ground status 4.4mm grounding socket for adding a ground connection "intelligent" connection will not create a ground loop in system that is already grounded surge protection shuts off power to gear plugged into parallel AC outlets when over-voltage is detected surge protection maximum: 30,000A @ 1000V/10µS operating voltage: 90V - 265V 1-5/8" diameter, 4-1/8" length weight: 0.24 lbs. warranty: 1 year What's in the boxAC Power conditioner User manual 3 Easy Steps About this itemWritten by Crutchfield's Jeff MillerPlug-in power conditioner that cleans up the noise The iFi Audio AC iPurifier plugs into an AC outlet and helps drown out power line noise, so your audio gear performs the way it should. This tube-shaped power conditioner connects in parallel, rather than in line. Plug it into an unused AC socket on the wall outlet or component that is powering your gear. Special circuitry helps filter out unwanted hums, distortions, and high-pitched tones caused by messy and erratic line noise. This noise can originate from electricity's long trek through our aging power grid, or get backwashed via larger home appliances. iFi uses powerful active noise cancellation to reduce that line noise by over 40 decibals.