The AntiCrak Fibre 13mm 500g is a premium Alkali-Resistant Fiber used for concrete crack control or gypsum casting. Low percentages of this fiber will impart improved strength and chip/crack resistance on your FMG castings. Can also be used as a premium product when hand laying FMG in replacement of the 20-40 strands. The strand properties are 12mm long, 14 micron diameter filament and 45 strand tex. This product is sold in 500gm quantity in a plastic tub.