Please buy with confidence and PLEASE leave a product review. THANK YOU, we appreciate your business.  After military retirement, we started a small EO/Bottle/roller business and know the value of quality products for our expensive and valuable Essential Oils.  We are located in South Carolina and only specialize in rollers/caps and PURE Amber and Cobalt Blue roll-on bottles with U/V protectant and sample bottles for essential oil and perfume products.  We have redesigned our products to work better, longer, and safer for our customers. 
In each package, you will find 12 roller inserts and caps for most essential oil 5 and 15ml bottles with a neck opening of 11mm and instruction card on how to seat the ball prior to first use.
For package contents and instructional usage, please see the video below.   
NEW DESIGN AND MATERIAL as of 3/2020: Roller Inserts have been redesigned to fit tighter into the bottleneck. The black collar material on the insert has been resized to ensure the balls do not fall out.  The black collar can be removed for cleaning in warm water and soap for re-use with different oils or blends.
Roller Special Feature:   In the event, the black cap is left off after roller use, after 1 minute, the ball moves upward and seals the bottle so your oils will not evaporate.   It is best to place the cap back on the bottle after use.  
When you get your rollers, prior to first use, the insert needs to be seated with the ball.   SEE 54 SECOND VIDEO BELOW!
ROLLERS FIT BOTTLES FROM: doTerra, Young Living, Planet Therapy, Rocky Mountain, and Mountain Rose bottles.
STAINLESS ROLLERS are DESIGNED for MID-GRADE to THICKER oils while GLASS ROLLERS are DESIGNED for the THINNER GRADE oils,  perfect for anything with FCO or Blends.