20mm All In Ballast Concreting Ballast Marine dredged for concreting Delivery Description 0/20mm All In Ballast is a primary sea dredged aggregate. It is a blend of 0/4mm Sharp Sand and <20mm Gravel used for making concrete; it is also used as a general drainage fill for construction projects. Other Products View Allicon-button-arrow-green 4/10mm Shingle Pea Shingle Driveways Drainage Runs Decorative Amelioration View Product 0/6mm Horticultural Grit Neutral ph Drainage Opens Clay Soils Marine Dredged View Product 20/40mm Shingle 40mm Shingle Green Roofs Driveways Drainage View Product 2/6mm Shingle Grit Shingle Angular Drainage Mulching View Product