1.[Heavy Duty]: It is a heavy duty safety pin, and it's designed to take a surprising amount of strength to open, 30 grams a piece safety pin, not suitable for normal clothes. 2.[Family Daily Use]: It's usually used for heavy duty laundry, hanging heavyweight stuffs, heavyweight material like canvas, leather, vinyl and upholstery. 3.[Fine Material]: Made of stainless steel, which creates rustproof and sturdy pins. For baby's safety, so it was made with locking closure. 4.[Updated Sharp Design]: The Heavy Duty Safety Pins are great for outdoor gear. Some reviewers comment negatively on the lack of sharp point, therefore, we improve our technology to make the pin sharper.