Abstract: Apparatus for inserting elastic strips into elastic leg diapers in accordance with the improved elastic leg disposable diaper and process for manufacturing same disclosed in co-pending U.S. patent application Ser. No. 85,372, filed concurrently herewith, and assigned to the assignee of the present invention, wherein elastic strips are adhesively secured continuously along the longitudinal edges of the disposable diaper and are alternately secured in stretched condition along the crotch area and in relaxed condition along the outer waist areas to form gathered and extendible side portions in the crotch area for elastic compliance to the legs of the wearer including mechanisms for alternately stretching and relaxing predetermined lengths of the continuous elastic strips.