Tronics Front & Back Pressure Sensitive Labeler TRonics Front and Back Pressure Sensitive automatic labeler. Pressure Sensitive labeler with Front and Back labeling heads with 4 1/2" conveyor includes: product spacing chain and speed controlled top hold down belt. Youtube: https://www.youtube.com/watch?v=2p4SLS8GATg Model TDS 031 DE Serial number 1707981576.