1. Size : : 4G(1.6mm) * 5/8"(16mm) * 5mm, This Size Is Suited For Nipple And Tongue. If You Have No Idea, Please Ask Your Piercer Or Contact Us. 2. Buying Guide : : jewelry is made of ASTM F136 titanium and certified by SGS, which is Hypoallergenic and 100% nickelfree. If you suspect you have a problem with jewelry, it may be worth having allergy testing performed by a dermatologist or allergist. And you can take our Jewelry to your piercer and testing group. 3. Aftercare : : body jewelry is suitable for a fresh piercing. When you get a fresh piercing, you should care about it and make it dry and clean. Do not touch and press it. 5. Great Idea : : The Straight Barbells are wearing different piercings, like Nipple, Tongue, Cartilage, Dimples and Industrial. It will be the best idea for yourself or your friends and families on the Anniversary, Birthdays, Christmas, Valentine's Day, and Mother's Day. 4. Detail : : Jewelry has strict standards in making Jewelry, whose titanium jewelry will be brighter than others owing to over 72 hours of polishing, and the thread is not easy to get loose.