New Custom Building Material: Dry Polymer enhanced Non Sanded Glow in the Dark GROUT - 1 Lb.(500 grams) 1. Based on the Portland Cement. 2 Ready to use just mix with water. 3 Provides a grout joint that is dense, hard and durable. 4 For narrow joints (1/8" [3 mm] or less) Properties: Day Color ( normal) - White ******* (actual colors may vary slightly from image)******* Glow in the Dark Color: NEON GREEN After glow time up to 6 hours for 15 minutes of charging time. Can be recharged unlimited times using any light source. Safety: Non-toxic, Non-radiation. Light sources: Sunlight, Fluorescent and halogen lamp, black lights, typical household incandescent light bulb, etc. Mixing instruction. Mix well: use 250-300 ml cool water for 1 kg of grout. Mix prior to taking out desired amount. Allow mixture to sit on the container for about 5-10 minutes, than remix before using