Golden Artist Colors Additives 4 fl. oz Acrylic Paint Retarder | JOANN
Amazon.com: U.S. Art Supply Acrylic Retarder Acrylic Medium, 200ml Tube (6.7 Ounces) - Mixed with Color gives you longer Working Times : Arts, Crafts & Sewing
Tri-Art Acrylic Retarder - 1 L - Walmart.com
Golden Retarder - Acrylic Paints
Slow Down Drying Time with the Best Retarders for Acrylic Paint