【Overview】: The Generator interlock Kit Compatible with Cutler Hammer BR Series 150 or 200 Amp panels. The Spacing between main and branch breaker is from 1 1/4–1 7/16". Before buying, make sure the model number and spacing is correct. 【Package includes】: 1 Interlock Panels, Matching drill bit, 1 Generator Start-Up Procedure Label, 3 Shoulder Screws, 3 Hex Nuts, 5 Remind Label, 2 Zip Ties, Installation and Usage Instruction . 【Application scenarios】: Our kit provides a easy and safe solution when inconvenience caused by unexpected power outages. The interlock kit prevents Municipal electricity and generator supplies from being on at the same time, avoid the inconvenience that may be caused by unexpected power outages. It is used to safely direct generator power to any circuit in your home, while ensuring that you have safe access to all your household appliances. 【Professional and safe】：We specializes in Generator Interlock Kits. We produce high-quality products to provide safety for you and your family. Electricity safety is no small matter, this is our responsibility. 【Worry-free after-sales】：Whatever the reason, you are not satisfied, you can request for replacement . Our products are backed by Lifetime warranty. At the same time, we have professional customer service, 7x24 hours to answer your questions. generator interlock kit allow safe backfeeding of a home through a portable generator during power outages. It eliminates unsafe generator backfeeding situations that could potentially electrocute electric power company workers or destroy the generator. Our devices will allow only one main circuit breaker to be in the ON (I) position at any time. The bracket slides between the handle of the utility main circuit breaker and the handle of the generator supply main circuit breaker.