A key and key holder combination has the overall form of a credit card so that the key and holder can be kept in a wallet for emergency use. The key (1) is injection moulded from a plastics material able to withstand the mechanical stresses to be imposed on the key and the holder (2) is separately moulded from a relatively inexpensive plastics material. The key is connected to the holder by hinges (4,5) in a manner which permits free rotation of the key relative to the holder about the hinge axis. Means (6,10) are provided for retaining the key and holder co-planar until the key is required for use.