The lightweight of this Universal Shaft is achieved by reducing the propeller shaft diameter from 4.2mm to 3.4mm (two piece set). The weight for the standard shaft is 35g compared with the lightweight shaft 29.5g (one shaft), a weight saving of 5.5g. Which means with all four shafts assembled, you can save a total of 22g. The above image shows two Lightweight Assembly Universal Shafts.