Peppermint oil extract is the chemical, they aren't big fans of the oil. I removed all dead panels on mine and used low expansion Great Stuff sealer at the plumbing runs especially the 8"x8" hole they cut for the pump, water line, and HW bypass area. Another hole was at the power cable/converter location, the wiring runs to the underside the trailer via a 4" hole. I did this last year with great success. In the front access door near your battery there are open holes behind the battery that run to the underside, seal those puppies up, too!
The glue traps work great if you can check on the trailer a few times a week. Once winter sets they are generally NOT needed. It is the fall that sees the greatest mouse activity as they nest for the winter and make babies!!!
2013 Jayco Eagle 334RBTS
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