The 30ML Clear Dropper Bottle with 18MM PP Knurling Dropper in Black features a glass tube, silicon black rubber teat, and a wiper plug for smooth, controlled dispensing. The knurled black dropper ensures a secure grip, while the wiper plug minimizes leakage and provides a secure seal. The clear bottle allows easy visibility of contents, making it an ideal choice for oils, serums, and other cosmetic liquids.