This new semi-automatic line assembles and tests the fire detector buttons. An interesting feature of this line is the 3D printed tricky shaped bearing, in which individual parts are placed. The operator places this bearing in a pallet on a belt conveyor, which transports this parts through all assembly and testing stations. In these stations is the unfinished part handled from and to the central conveyor by a 6-axis robot. The input parts required for assembly are taken from vibrating feeders by two 4-axis robots. From the output conveyor are the final parts removed by an operator, who finally checks and packs them.