This set is for pressing bearings into a Trek BB90 frame. Our drift sets are designed in such a way that it is close to impossible to damage the bearing races during installation. Every set consists of two frame drifts and a frame guide. The guide centers the tool in the frame so everything stays lined up straight. Born out of a frustration with the current offers on the market, we decided to tighten up the tolerances and design a set around the Park Tool HHP-2 bearing press, the most common tool used by professional mechanics.