Abstract: There is provided a slide fastener including a fastener chain and a slider. The slider includes upper and lower blades, a front end wall having a first front mouth and a second front mouth provided below the first front mouth, and one rear mouth. The slider is movable in a first direction to engage a pair of element rows, and in a second direction to disengage the pair of element rows. Each element has a base portion fixed to respective fastener tapes and a head portion configured to be engaged with the opposing elements. The head portion has a first head portion arranged at a side of upper surfaces of the tapes and a second head portion arranged at a side of lower surfaces of the tapes. The first head portion is formed to be offset from the second head portion in the first direction.