The conversion of two stock E-2s with two BMW 132 F radial engines led to the Do 17 J-1 and Do J-2. These aircraft were used to evaluate the BMW 132 engine in flight tests. The aircraft were the prototypes V18 (WRK No. 2021) and V19 (WRK No. 2022). Trialos began at the end of 1937.
