The Park Tool BBT-18 Bottom Bracket Tool is a heavy-duty, investment-cast tool specifically designed for installing and removing Shimano Octalink and ISIS Drive bottom bracket cups with eight external notches. Its robust construction ensures long-lasting use and precise tool engagement, making it perfect for both installation and removal tasks. The BBT-18's eight-notch design provides a secure grip, ensuring efficient and safe maintenance of your bottom bracket. Ideal for professional and DIY bike mechanics, this tool offers the reliability you need for handling various bottom bracket cups.