pressure foot 36 comprising a plane surface 44 rigidly or flexibly attached to the cylindrical shaft 38 a handle 43 fixedly attached to the handle end of the cylindrical shaft 38 and a means for urging the pressure foot 36 against the color sample 2 or the color sample stage 7 such as a helical compression spring 37 coaxially mounted compressed on the cylindrical shaft 38 between the pressure foot 36 and the cylindrical journal 42 the dimensions of the pressure foot surface in contact with the color sample are preferably at least a large as the optics port 22 of the colorimeter 1 the pressure foot 36 is preferably a lightweight metal such as aluminum with a smooth machined surface however any material providing the necessary strength and rigidity may be used the support arm 41 and handle 43 are preferably a lightweight metal such as aluminum however any material which provides sufficient strength and rigidity may be used the cylindrical shaft 38 and cylindrical journal 42 are preferably metal however any material providing sufficient strength and rigidity and which permits the cylindrical shaft 38 to slide within the cylindrical journal 42 may be used the cylindrical shaft 38 fig2 and 3 is of sufficient length and the compression spring of sufficient relaxed and compressed length and.