A labyrinth channel for reducing pressure and/or flow rate in a liquid flowing in the channel, the labyrinth channel having a bottom surface and first and second opposing walls and comprising: a first array of spaced apart first baffle teeth that have non-parallel upstream and downstream faces and extend from the first wall towards the second wall to terminate in an end； and a second array of spaced apart second baffle teeth that have non-parallel upstream and downstream faces and extend from the second wall towards the first wall to terminate in an end； wherein baffle teeth in different arrays have a substantially same shape and upstream faces of closest baffle teeth in different arrays are different and/or downstream faces of closest baffle teeth in different arrays are different.
