The Federal Trade Commission ("FTC" or "Commission") issues final amendments to its Trade Regulation Rule Relating to Power Output Claims for Amplifiers Utilized in Home Entertainment Products ("Amplifier Rule" or "Rule"). The amendments require sellers making power-related claims to calculate power output using uniform testing methods to allow consumers to easily compare amplifier sound quality; prescribe disclosure language that improves differentiation between power output claims that comply with the Rule's testing methods and those that do not; and modernize as well as clarify Rule language considering the foregoing modifications. Additionally, the amendments formalize prior Commission guidance on applying the Rule to multichannel amplifiers.