Starbrite Ultimate Fiberglass Stain Remover - Gel FormulaStarbrite's Ultimate Fiberglass Stain Remover is a gel formula sticks where applied for maximum cling time and cleaning power. Use this stain remover to get rid of the toughest stains including rust, dried fish blood, and leaf stains. Features: Gel formula clings where applied for maximum cleaning power; Removes "yellowing" and tough waterline stains; Completely covers stains to penetrate and dissolve them; Specifically formulated to remove the toughest stains, including rust, dried fish blood and leaf stains; Works on all fiberglass and painted surfaces; ideal for vertical surfaces; How to Apply Starbrite Ultimate Fiberglass Stain Remover - Gel Formula Spray directly onto area to be cleaned.; Allow to soak in until stain disappears and then rinse thoroughly with fresh water.; Stubborn stains may require a repeated application that is allowed to soak in for several minutes; Follow up with light scrubbing and rinsing.; Not for use on fabric.; Click to Download Starbrite Ultimate Fiberglass Stain Remover MSDS