[. . . ] Notice for the USA This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. [. . . ] If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures: · Connect the equipment into an outlet on a circuit different from that to which the receiver is connected. Any changes or modifications made to this device that are not expressly approved by Philips Consumer Lifestyle may void the user's authority to operate the equipment. Frequency Receiving distance Transmitter power input Receiver power input Receiver power output 315MHz 50 ft in open area (The number may be variable according to the environment and battery condition. The nail or screw head must be extended at least 3/16" out from the wall. [. . . ] Operation is subject to the following two conditions: (1) this device may not cause harmful interference; and (2) this device must accept any interference received, including interference that may cause undesired operation. [. . . ]