Complex sentence: Based on information passed to them through the Duquesne Spy Ring, the Luftwaffe developed the Lotfernrohr 7, which was operationally almost identical to the Norden, but much easier to use.
Split into simpler sentences: Based on information about the Norden passed to them through the Duquesne Spy Ring, the Luftwaffe developed the Lotfernrohr 7. This was operationally almost identical to the Norden, but much easier to use.