Extension cords are for temporary use only. Never use extension cords for appliances like refrigerators, microwaves, or air conditioners. Never overload a power strip or surge protector. Do not plug refrigerators, microwaves, air conditioners, or other appliances into a power strip or surge protector. Do not run the cord for the power strip under a rug or through a wall. Unapproved cube adaptors should never be used. Never overload a receptacle.