DIN 7601 is Compression couplings with ball-type nipples - Complete unions and survey. This standard including:
Form A is male stud to tube connector, with standard DIN 3870, DIN 3863, DIN 7603 and DIN 7647.
Form B is Tube to tube Union connector, with standard DIN 3870, DIN 3863 and DIN 7631.
Form Q. is banjo fitting connector, with DIN 7642, DIN 7643 and DIN 7603.