Regular Brown Fused Aluminum Oxide ESK, RBT 9 calcined, angular grain shape ZESK, RBT9 calcined, blocky grain shape OSO for resinoid bonding, angular grain shape ESCC calcined, angular grain shape, ceramic coated ZESCC calcined, blocky grain shape, ceramic coated BZESK high temperature treated, blocky grain shape BZESCC high temperature treated, blocky grain shape, ceramic coated GF *) blocky grain shape GFK *) blocky grain shape, silane treated GFC *) blocky grain shape, ceramic coated ASF *) sharp grain shape ASFK *) sharp grain shape, silane treated