Product Feature: Fitment: This is a general purpose spring tester with a wide range of applications. Material: This product is made of high-quality stainless steel, aluminum alloy and rubber, which is durable and has a longer service life. Advantage: This mini style is more convenient for carrying and storage, affordable and practical. The hexagonal design body is very versatile and works well in a vice or mandrel press. There is a high-quality rubber protective cover on the outside of the case, which is not easy to break. The tester's performance is excellent, the scale is accurate, and even small changes can be measured. .