Compatibility Assurance: Designed to function seamlessly FOR Cutler Hammer BR and CH Series main 150 and 200 AMP panels, ensuring a perfect fit and faultless operation. This vital compatibility eliminates issues during installation or use, enhancing your safety and convenience. Precision Spacing Requirements: Requiring a precise interval space of 1 1/4 - 1 7/16 inches between the main and generator breaker, this kit ensures safe operation. Precisely measuring the spacing is critical for optimal performance; double-check model numbers and dimensions for a setup. Enhanced Safety Features: Equipped with a manual transfer switch device, this kit ensures the safe back-feeding of power from a portable generator to your panel and home lines. It effectively prevents both utility and generator supplies from being active simultaneously, safeguarding against electrical hazards and equipment damage. Colour:Silver Material:Metal Package Contents: 1 * Generator Interlock Kit(Drill bit color is random, no specification is accepted) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.