Control box, in particular for adjustable items of furniture, such as vertically adjustable tables for example, comprising: a control box housing and a mains plug in a wall of the control box housing, wherein the control box housing has a strain relief device for a mains cable with a main cable socket for connection to the mains plug, characterized in that the strain relief device has an, in particular channel-like, mains cable clamping guide which is arranged upstream of the mains plug in the insertion direction of the mains cable socket and so as to run transversely to the insertion direction in the control box housing and therefore below the mains plug such that the mains cable socket, when it is inserted into the mains plug, at least partially closes the mains cable clamping guide on the top side in such a way that the associated mains cable does not move out of the mains cable clamping guide.