How level bombing was done with Pe-2 and Tu-2?

[RB]

Thanks for the answer RB. I see the PBP-1, this is a standard gunsight, good for steep dive bombing, but could the pilot use it for level bombing? How does he enter the speed and height of the bomber (you need at least this for level bombing)?

Can you tell me what are the devices shown in the first pic below? I see that the first one is used for dive bombing and the second one is used for dive and level bombing. Can you tell me what they are?
Thanks again.

According to POH PBP-1 can be used for level bombing; however, the level bombing technique by itself is not explained.