4oz Castor Oil Includes Bonus Brush Kit – 100% Pure USDA Organic. Castor Oil For Hair Growth – Making Your Eyelashes & Eyebrows Full Again! There is nothing like waking up to long eyelashes and stunning eyebrows. The best time to treat your eyelashes or eyebrows is before you go to bed. Just a small dip on your lash line or eyebrows and it could leave your eyelashes and eyebrows looking healthier than ever!