Gensafety Generator Interlock Kits are proudly made in the USA and are guaranteed to fit and operate perfectly every time. The Model BR100 fits Eaton / Cutler Hammer 100 amp and 125 amp panels with adjacent main and generator breakers as shown. The main and gen breakers can be left or right side mounted as long as they are next to each other. These interlocks are precision CNC machined from solid T6061 aluminum billet and are then color anodized for long life and smooth operation. No stamped or plastic parts here! Unlike many imports, these interlocks are precision machined and fit perfectly every time. Should you ever require customer service youll find that we are extremely responsive and helpful. Everything necessary for the installation is included. These are VERY high quality kits. Once you install a GenSafety Interlock Kit you wont want to use any other brand!