Tak snad sám dokážeš najít text "days".

$(this.el).html("<div>" + this.leadingZeros(data.days, 3) + " <span>days</span></div><div>" + this.leadingZeros(data.hours, 2) + " <span>hrs</span></div><div>" + this.leadingZeros(data.min, 2) + " <span>min</span></div><div>" + this.leadingZeros(data.sec, 2) + " <span>sec</span></div>");