Inspection tools are widely used in today's industrial production assembly self-inspection, which can detect geometrical dimensions and shape and position dimensions, screen bad products for enterprises, control product quality and production efficiency, and achieve the purpose of saving costs. The inspection tools are divided into special inspection tools and non-standard inspection tools. The non-standard inspection tools are mainly introduced here. Since there is no universal design standard for products in each industry in industrial production, the products designed by each enterprise are somewhat similar and some are quite different. When inspecting batches of precision product parts, the subtle changes in the tolerance zone determine the quality of one or a batch of products and the possible loss. First of all, it is particularly important to customize the inspection tools according to the drawings. With the continuous improvement of modern manufacturing technology, companies are encouraged to design more sophisticated and efficient products, such as automotive, aviation, medical equipment and other industry products, which contrasts the prospect of non-standard inspection tools.