QPR forward Sebastian Polter has joined Union Berlin of the 2. Bundesliga on a three-and-a-half year deal for a fee of £3 million.
Polter spent the 2014-15 season on loan at the German second-tier club where he scored 14 goals in 29 appearances before joining QPR on a three year deal.
The 25 year-old joined from Bundesliga side Mainz in 2015 and scored 11 goals in 56 appearances during his 18-month spell at Loftus Road.
The former Germany under-21 international had not featured for QPR since mid-December.