U1 -
fighter bomber with ETC 501 centerline rack and without MG
FF's. Older BMW 801C-2 engine.
U3 -
same as U1 with BMW 801D-2. This variant became later F-1.
U4 -
reconnaissance fighter with 2 X RB 12.5 /7X9 cameras. No MG
FF's
U8 -
long range fighter bomber, 2 X 300 liter droptanks, ETC 501
centerline rack, only armament was 2 X MG 151/20. This became
later G-1 variant.