Perfume Studio® Metal Balls for Roll on Bottles - Bulk Set of 48 Units - Replaces Roller Tops for Roll-on Bottles with Stainless Steel Metal Balls. Fits Roll on Bottles with a .63 in / 16 Mm Inner Neck Diameter

Replacement Roller Tops for Roll-On Bottles with Stainless Steel Metal Balls (48 units) - Fits Roll On Bottles with a .63 in / 16 mm Inner Neck.

Only use metal balls with pure, uncut oils! Will not work with high lubricant essential or body oils: If ball pops out of your roller, you most like are using oils that are cut with other carrier oils such as coconut, almond, dpg, etc.