"Scrub smarter, not harder, with the Drillbrush Power Scrubber Edge Brush Kit. This 4-piece drill brush kit works wonders on a variety of water-related objects and surfaces. It's great for boats, pools, canoes/kayaks, hot tubs, and plastics. The edge brush gets into grout lines and grooves in pool tiles to make quick work of tasks that once seemed neverending. The 4"" flat brush easily cleans large, flat areas such as pool tiling or boat hulls. Tilt it to a 45 angle for your stubborn grout lines. The bullet-shaped original brush gets in curved spaces such as props and the inside of a filter housing, making hard-to-reach spots and tight corners a breeze. The 2"" detail brush works great on small spots any cleaning can overlook, letting you finish the job right. Each brush has medium stiffness, a steel shaft with rust-resistant nickel plating, strong polypropylene plastic block for better durability, and a 1/4"" quick-change shaft for easy use in virtually any drill or impact driver. Great for DIY enthusiasts, professional detailers, and anyone looking to protect their investments, this power drill brush set lets you clean like a pro. 4-piece drill brush set covering perfect for marine and other water-related applications Medium-stiffness, non-scratch nylon bristles Steel shaft with rust-resistant nickel plating Strong polypropylene plastic block 1/4"" quick-change shaft for use in nearly any drill or impact driver Edge brush for grout lines and grooves 4"" flat brush for large, flat areas or stubborn grout Bullet-shaped original brush for curved spaces and tight corners 2"" detail brush for the finishing touches"