These 1 fl oz (30 ml) Roll-on applicator bottle has a Large roller ball It comes unassembled for ease of filling Once filled simply 'snap' on the roller ball assembly A tight fitting cap keeps your product from leaking These beautiful blue glass bottles are a handy way to apply essential oils, blends, and massage oils to the skin-simply roll them on as needed 1oz Color Roll-On bottle, comes with Ball, housing and cap.The color makes the bottle color resistant to scrath marks