TEC 15030490 AccuColor 2.85 lb AccuColor Unsanded Silicone Acrylic Caulk Jet Black is a smooth, unsanded caulk that is formulated to precisely color-match TEC® AccuColor® grouts for flawless matching. Forms a tough, flexible, water and weather-resistant seal on most building materials, protecting your installation from moisture, drafts and rot. Contains a special silicone additive to promote greater adhesion and longer life.