Share with Others: Perfect for gift giving or handing out samples of your favorite essential oil blend. Protect Your Oils: Light blue color protects oils from UV light damage. Perfect for travel, and conveniently fits in your purse. Easy to Use: Roller bottles are a very handy way to apply your essential oils, no mess, just roll them on. Essential oil glass bottle is made of corrosion-resistant glass which makes it thick, smooth and anti-shock. Stainless steel roll balls: The roller balls are all stainless steel, they roll smoothly without getting "stuck" and they seal securely with the bottle mouth so there is no leakage.