Opening Act has the best function and retention in higher humidity environments while reducing time spent on touch-ups. Recommended humidity and temperature for optimum results: 40%-65% and temperature 69-72 degrees. Opening Act Adhesive is recommended for beginner lash artists that work in moderate to high humidity.This adhesive works best in humidity between 40%-65% and temperature 69-72 degrees. Opening Act Adhesive is recommended for beginner lash artists that work in moderate to high humidity. For low to moderate humidity, incorporate Glue Aid to help speed up dry time. For dry climates or during winter, a professional humidifier may be required. Specifications Retention Viscosity Color Fumes Structure 8+ Weeks Medium Black Minimal Flexible Dry Time(s):40-65% Humidity (2-3 sec) Shelf Life: Opened bottles: 30 days ; Unopened bottles: 6 months