【Compatiblity】This toothbrush head was designed to be compatible with Waterpik Complete Care 9.0 (CC-01CD012-2) and to be compatible with Waterpik Complete Care 5.0 (WP-862 WP-872 WP-882), Black.  【Curved Shape Bristle】 Shape of bristle is designed in curved shape thus the head can fit to teeth well. A great shape for efficiently brush and removing more plaque and stains. 【Well End-rounded】 95%-98% top of bristle have to be rounded after planting and cutting, which is a processing of must for protecting teeth when brushing in high vibration. The teeth enamel would get worn if bristle was not end-rounded   【Sanitary Packing】 Each toothbrush head equipped with dust cover then sealed into plastic bag and together packed in paper box. Three layers of protection avoid dust pollution during packing and transportation. Also, dust cover is perfect for travel, keeping your head free from germs & stains. 【Medium Bristle】 Plant 0.178mm nylon bristle, which are stiff enough to remove debris, but also soft enough that they don’t damage tooth enamel.