15-541-6 SPI Optical Comparator 16" x 9"SPI Vertical Optical Comparator Inspect your parts with surface and or profile illumination. This Optical Comparator is built with solid, stable steel construction. The X Y table positioning is done with ball screws (0. 1" rev), also with quick disconnect for fast positioning. The excellent quality optical system provides clear images and accurate magnifications. Specifications include 15. 9" x 8. 9" Table 10. 2" x 6. 3" Glass Stage Stage Travel 7. 8"