Abstract: The test kit includes a substrate and, welded or bonded thereto, a plastic sheet having blisters. One of the blisters is shaped as a siphon. The other blisters act as reaction vessels and also serve to receive and store a reagent. The test kit may contain a test strip in one of the blisters. The test kit is particularly suited for carrying out immunological tests, whereby the siphon markedly facilitates the procedure during the washing step.