SPI 12" Optical Comparator This Horizontal Comparator, or Profile Projector, is used with heavy parts or with shapes that require being in a fixed position. A light is projected horizontally onto the workpiece, and the profile shadow of the part is then projected onto the screen. Complete package includes the following... 10X, 20X, & 40X Lenses 2 Dial Indicators 0-1" Range, .001" Grads, Includes Cert of Calibration, # 22-300-8 0-2" Range, .001" Grads, Includes Cert of Calibration, # 22-310-7 12" x 3" T-Slot Stage 6" x 2.5" travel 12" Diameter Screen Rotatable screen with fine adjustment High & Low intensity profile illumination switch