A ladder clearance gauge for detecting clearance

The utility model relates to a ladder clearance gauge for detecting clearance, its characterized in that: it includes a handle the both ends of handle are rotated through a round pin respectively and are connected a measuring tape, two the measuring tape all be by the link to the free end echelonment of attenuation gradually, be located samely poor equalling of thickness between the double -phase neighbour's on the measuring tape ladder, be located the difference thickness between the double -phase adjacent ladder on the measuring tape is poor also equal, one of them thickness and another of the thickest ladder on the measuring tape difference on the measuring tape between the thickness of final thin ladder equals to be located samely thickness on the measuring tape between double -phase adjacent ladder is poor. One the thickness of the step on the measuring tape is 5mm, 4mm, 3mm, 2mm and 1mm in proper order, another the thickness of the step on the measuring tape is 10mm, 9mm, 8mm, 7mm and 6mm in proper order. The utility model discloses can extensively be used for the detection in the clearance in narrow and small space.