The special sampler RBP is a special solution for extracting samples from round-bottom trough conveyors (RBTF). The sample cylinder RBP with seal is extended on the outer wall of the RBTF. In order to take the sample, the cylinder retracts and product flows through the opening into the funnel and then into the sampling line. The quantity is defined by the time control or through the use of a pinch valve. To finish sampling, the cylinder moves back against the outer wall and the air valve generates a blast of cleaning air to minimise carry-over.