I have a few of those too as backup. The ultrasonic repellents work. No mess, no stink, no dead bodies, and no bait boxes. It's been 4 years now without any trouble.
For the trap bait, B.O.S.S. works well. No mess, no stink and it's organic.
I like the fact it's natural. I can't get electrical everywhere on the farm for the ultrasonic repellents. Better than the toxic D-con.
I lost 1 VR behind the dash as the mice made a nest and ate the wires! From that point on it was a planned war. Glad the wires were on the VR to the connector and not the tractor harness. A $32 fix. That nest took nearly an hour to remove properly. All the electrical ran thru that area for the lights, ignition, dash display lamps and the VR. The mice dropping and pee all went to the top of the VR. It corroded badly. Glad it wasn't found on the inside tray nor the steering shaft.
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