A clasp including a base connected to at least one end of looping member which has an upper opening at an upper side thereof and which has a front opening at a front side thereof; an arm which is supported by the edge of the base in a rotatable manner, which has a nail portion at a rear end thereof; and which makes up a loop by closing the arm; a push button embedded within the upper opening of the base and communicated with the nail portion of the arm; a first spring which applies a resilient force to the push button in the direction that the push button is projecting outwardly; and a second spring which applies a resilient force to the arm in the direction of opening the arm.