Single speed curious? The new Wheels Mfg SOLO-HG lineup is helping Shimano HG hub users get back to the basics with the simplicity and clean lines that a single speed offers. The brand is introducing the new SOLO-HG Conversion Kit, as well as SOLO-HG Cogs. And, as you may have guessed, "HG" stands for Shimano's Hyperglide freehub body, making the SOLO-HG kit compatible with Shimano HG only. While Wheels Mfg previously offered an HG conversion kit, it lacked the options and customization available with the SOLO series.