Special-shaped caliper for measuring profiles and pipes

The utility model provides a special-shaped caliper for measuring section bars and pipes, and belongs to the technical field of measuring equipment. Comprising a ruler, a fixed tooth part is fixedly arranged at one end of the ruler, a vernier is slidably arranged on the ruler in the length direction of the ruler, a movable tooth part is fixedly arranged on the vernier, the fixed tooth part comprises fixed teeth, the movable tooth part comprises movable teeth, and the fixed teeth and the movable teeth are located on the same side of the ruler. The side walls, close to each other, of the fixed teeth and the movable teeth are parallel and can be attached to each other, and the faces, capable of being attached to each other, of the fixed teeth and the movable teeth are provided with receding notches matched with each other. When the wall thickness of a product is measured from the end part of a pipe or a sectional material, the movable teeth and the fixed teeth of the caliper are clamped at the inner wall and the