Its made by coir yarn and are fully biodegradable and its mechanical strength to hold soil in place and prevent soil erosion.The netting breaks up run off heavy rains and dissipates the energy of flowing water. Product GSM (400,600,700,900), Dimensions: Length x width: ( 50 meters x 4 meters), Package: NUmber of rolls in 20 feet containers: (gsm 400- 64 rolls)(gsm 600- 40 rolls) (gsm 700- 36 rolls)(gsm 900- 28 rolls): NUmber of rolls in 40 feet containers: (gsm 400- 240 rolls)(gsm 600- 140 rolls) (gsm 700- 130 rolls)(gsm 900- 96 rolls):