There are many different sizes and even shapes of spoke nipples, some of which are very similar to one another. Nipples are typically made of soft material and can be easily damaged by the wrong sized spoke wrench (or poor-fitting off-brand wrenches), so having the correct wrench is important. Luckily, Park Tool offers a full range of spoke wrenches in virtually every size found on a bike. Here's a selection of the spoke wrenches we make to help you stay true: