the two this may be done to bring the wires together up to a point along their longitudinal axis and help reform the bundled condition including when the testing operation is complete another form of retainer may also be provided in the nature of a plug 106 for associating the wires with a particular connector on a testing apparatus such as device 10 referring to fig1 another aspect of the invention relates to the electrodes 200 used in connection with the wires 202 for performing certain tests and in particular those that require the use of a viscous liquid substance typically collodion in gel or paste form in order to help form an electrical connection with the particular portion of the body involved in the testing usually this substance is applied to the body and then the electrodes which as shown may be disc shaped connected to it which is a relatively messy and involved undertaking to avoid this and with reference to fig1 the substance may be pre disposed in the electrode 200 prior to use such as within a cavity 200 a the cavity 200 a including the substance s may also be covered by a removable cover 204 such as a thin flexible substrate that helps retain the substance in place prior to use the cover 204 may be attached to the electrode 200 such as by.