I use a tender on two of my cars because they don’t get driven weekly (one is resting through winter now).

I used to use the cig lighter and run the cord through a cracked window or across the door rubber, then I started doing under hood connections since the lighter isn’t hot on all cars. But I leave the hood up so I don’t get in a rush and drive off with the tender still connected!

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Mike

2005 e53 X5 4.8is 169k miles
2018 f90 M5
2018 Volvo XC60