✔[Heavy Duty]: It is a heavy duty safety pin, and it's designed to take a surprising amount of strength to open, 31 grams a piece safety pin, not suitable for normal clothes.
✔[Family Daily Use]: It's usually used for heavy duty laundry, hanging heavyweight stuffs, heavyweight material like canvas, leather, vinyl and upholstery.
✔[Fine Material]: Made of stainless steel, which creates rustproof and sturdy pins. For baby's safety, so it was made with locking closure.