Reduce surface tension and increase paint flowAdditives serve a similar function to mediums. The difference is that additives don't contain acrylic
GOLDEN Acrylic Additives
Golden 0003580-5 8 oz Artist Colors Acrylic Retarder
Golden Isolation Coat
Golden Retarder - 4 oz.
Golden Acrylic Medium, Retarder, 16 Oz
Golden Gel Mediums
Golden Retarder - 16 oz.
Golden 0003580-5 8 oz Artist Colors Acrylic Retarder
GOLDEN Silkscreen Medium
Golden Acrylic Glazing Liquid