An improved knife assembly for use with a header of an agricultural harvester. The assembly includes a knife head, a knife back and a plurality of sickle sections fastened to the knife head and knife back. The sickle sections include first and second portions where a second portion of one knife section overlaps a first portion of an another sickle section when the knife sections are arranged in adjacent relationship. The overlapping areas of the adjacent knife sections include aligned though holes which shared fasteners. The resultant construction reduces the overall knife assembly mass thereby leading to increased cutting speeds and corresponding harvester ground speeds. Additionally, the time and labor associated with manufacture and maintenance is reduced while the assembly strength and force distribution capability is enhanced.