Park Tool SW-0 Bicycle Spoke Wrench Our iconic spoke wrenches have been a mainstay of our product lineup since we introduced them over 40 years ago. With their simple design and professional quality, they're still the favorite of bike mechanics around the world. Each Park Tool SW-0 is made in the USA, and is precision-stamped, hardened and nickel plated for long service. Park Tool Spoke Wrenches are vinyl-dipped in one of four colors indicating the size at a glance. The SW-0 is sized for 3.23mm (0.127") nipples. These nipples are often found on higher-end bikes. Typical compatible nipple brands include DT Swiss, Sapim, Wheelsmith, Pillar, and many others. Always measure to be sure. ALWAYS TRUE There are many different sizes and even shapes of spoke nipples, and 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 how to determine the correct wrench for your bike, and a selection of tools we make to help you stay true: ALWAYS TRUE There are many different sizes and even shapes of spoke nipples, and 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 how to determine the correct wrench for your bike, and a selection of tools we make to help you stay true: SIZE MATTERS Most square nipple sizes are within 1mm of each other, so a wrench that is too big may still seem like it fits. However, nipples are typically made of brass or aluminum. Both are a relatively soft material and can be easily damaged by the wrong sized spoke wrench (or poor-fitting off-brand wrenches). MEASURE TWICE The best method to determine the correct spoke wrench size is to use a caliper and measure the nipple across the wrench flats. Don't worry about the size of the spokes themselves - spoke gauge is not correlated to nipple size. TOP TWO For square nipples, there are several size possibilities, but the two most common are nominally 3.2mm (Park Tool SW-0) and 3.5mm (SW-2) when measured across the flats. Use the smallest wrench that fits on the nipple. SW-0 Spoke Wrench SW-40 Four-Sided Spoke Wrench SW-20.2 Professional Spoke Wrench SW-7.2 Three-Way Spoke Wrench SW-9 Double-Ended Spoke Wrench Spoke Nipple Size 3.23mm (0.127") 3.23mm (0.127") 3.23mm (0.127") 3.23mm (0.127"), 3.30mm (0.130") & 3.45mm (0.136") 3.23mm (0.127") & 3.45mm (0.136") Special Features Four-sided wrench for added security Investment cast precision-machined steel construction 3 most common sizes for versatility Ergonomic double-ended wrench Park Tool SW-0 Park Tool SW-1 Park Tool SW-2 Park Tool SW-3 Spoke Nipple Size 3.23mm (0.127") 3.30mm (0.130") 3.45mm (0.136") 3.96mm (0.156") Typical Applications Higher-end (>800 dollar) bicycles Older (pre-1990s) American bicycles - not as common Department store bikes/low-to-midrange bikes Select Shimano wheels, hub-drive e-bikes, heavy duty bikes TRUSTED SINCE 1963 Since our origins in the back of a bike shop in 1963, it has been our sole mission to design and manufacture high-quality tools that empower mechanics and riders of all skill levels to service their bicycles. As with our other 500+ tools, our wheel truing tools are a product of our decades of experience and expertise in the industry, in the shop and on the trail.