I love my Microsoft Surface Pro 3, but third party accessories are sometimes hard to find. Microsoft themselves doesn’t even make a car charger, which, thankfully, Amsam has addressed.
The Amsam Microsoft Surface Pro 3 / Pro 4 Car Charger Adapter accepts 12 – 24V input and outputs the expected 12V, 2.58A. As you would expect, there is short circuit and overload protection built-in. Compatibility is with the Surface Pro 3 and Surface Pro 4, although not with the Surface Pro 4 with M3 processor.
Now, for a negative. While the cord is of sufficient length, the magnet that holds the cord to the Surface Pro is a bit on the weak side, so it doesn’t stay in quite as securely as it probably should.
While the Amsam Microsoft Surface Pro 3 / Pro 4 Car Charger Adapter is not perfect, the unique value proposition still makes it worth considering for keeping your Surface Pro charged in the car.