I’ve been using Aukey’s Flush Fit Dual Port USB adapter since early 2016. Once you push it into the car’s “cigarette lighter” hole, it’s close to a flush fit. It could be a chore to pull it out, but I’ve never had a reason to. It’s regularly $9 but if you use the Amazon code AUKECAR7 it costs $7.
Tiny flush-fit dual USB adapter for cars
