Danish pop/schlager vocal quartet formed in 1956. Original member left in 1958 to pursue a successful solo career and was replaced by , better known under his stage name . After the quartet split in 1963 served as a bar pianist for some years before becoming Denmark's most popular schlager artist of the first half of the 1970's.
In 2010 a tribute quartet with singers and as well as actors and started touring as "More Jacks".
Members
- Otto Brandenburg
- John Mogensen
- Bent Werther
- Flemming Rasmussen
- Poul Rudi
- Kaj Berglund
- Bjørn Thorsøe