Fishstone, Concrete Countertop Supply's Optimum 380 is a modified polycarboxilate high range water reducing admixture formulated to deliver high spread rates with "self placing" properties. Optimum 380 can deliver higher early strength, improved workability and surface densification with lower dosage rates. Optimum 380 is available in 1-quart, 1-gal., 5-gal. and 55-gal. sizes.