Abstract: In addition to the normal weight display, a display for a balance has a number of other areas in each of which a word indicative of an operation which has been or may be carried out is displayed. The words to be displayed are arranged on an exchangeable card which may be inserted into the balance. Light from each particular area of the card is transmitted or blocked by application of control signals to a liquid crystal which is interposed between the card and the operator's view. The control signals are applied in accordance with the program being carried out and with signals derived from operator controlled keys. The display may be used to direct the operator, since only the operations possible at any particular time are visible. The cards may be imprinted in any language or type of letters, without requiring any change in the remainder of the balance or display.