A safety pin and magnetic key to actuate, loosen or tighten the pin, which incorporate means to automatically and by magnetic attraction connect a body of a cavity of a head of the pin, formed by a fixed part of a rod and by a movable part, by applying the key. The safety head of the pin delimits a totally...http://www.google.com/patents/US20020029596?utm_source=gb-gplus-sharePatent US20020029596 - Safety pin to be actuated by a magnetic key
