The Official Online RBS 6 Nations Store is open. The store has everything you need to get behind your team during the RBS 6 Nations, plus the store is now fully stocked with a much wider range of rugby merchandise.
The 27-year-old earnt a call-up to the England Saxons squad in 2006 and was Worcester's player of the season for 2006-07.
Warriors director of rugby Mike Ruddock said: "Kai is reaching the peak of his powers. He is an intelligent athlete who really is Mr Dependable and is hugely respected by the players."