Ph colorimetric test strips used with the locking colorimetric pallets

The present invention relates to a plate for a color chart for a colorimetric PH paper with lock belonging PH test paper colorimetric BACKGROUND apparatus comprising a standard comparison PH test paper color chart and the fixing plate placed vertically in the left vertical fixing plate defines a first chute, the chute is provided with a first slider that slides freely up and down, corresponding to the first chute is provided with a clamp for clamping the PH test paper on the side of the fixed board, plywood by together with the slide bolt, a standard color card standard several different colors than the color card blocks, than the standard pitch like block color cards vertically disposed first chute to the right of the fixed plate, the fixed plate a positioning mechanism is provided with a transparent plate for a standard card protection than the transparent color, than the standard vertical fixing plate disposed between the color card with the first chute for positioning when the jaws move. Can be well protected without damaging the standard color card to the present invention, the standard does not require a large number of backup, when the color contrast is very convenient card.