Complex sentence: The Panzerfaust 3 can be fired from inside rooms and close spaces since it doesn't have too dangerous a backblast; the rear of the tube comes filed with plastic granulate and the blast effect is thus minimized.
Split into simpler sentences: The Panzerfaust 3 can be fired from inside rooms and close spaces since it doesn't have a too dangerous backblast. The rear of the tube comes filed with plastic granulate and the blast effect is thus minimized.