A device provides a hybridization chamber for hybridizing nucleic acid samples, proteins or tissue sections on a slide, and is an essentially rectangular body movable opposite the slide. The device includes a surface, lines for supplying and/or removing media, a specimen supply line and an agitating device. The agitation device includes at least one membrane which separates a pressure chamer to be fillable with a pressure fluid via one of the lines, from at least one agitation chamber connected via an agitation line to the hybridization chamber. The lines are continuously open so the media therein can permanently flow unhindered. Four such devices can be combined into a process unit for providing a hybridization chamber. Such unit is pivotable around an axis and has a holder with four seats, which is lockable in relation to a baseplate, one device being insertable into each one of the seats.