DRR-DTH Standard Changeover A standard changeover switch with a 39.67mm long x 5.33mm diameter (1.562" x 0.210") glass envelope, capable of high voltage and power switching up to 500Vdc at 30W. DRT-DTH Standard Changeover A standard changeover switch with a 39.67mm long x 5.33mm diameter (1.562" x 0.210") glass envelope, with tungsten contacts capable of high voltage and power switching up to 500Vdc at 50W. MDRR-DT Miniature Changeover A miniature changeover switch with a 14.73mm long x 2.54mm diameter (0.580" x 0.100") glass envelope, capable of switching 175Vdc at 5W. Sensitivity range 15-30 AT. MDSM-DT Miniature Changeover Surface Mount A miniature, surface mounting, changeover switch with a 14.73mm long x 2.54mm diameter (0.580" x 0.100") glass envelope.UL recognised and capable of switching 175Vdc at 5W.