Check the listing for details. Rare TWA Trans World Airlines Optical Comparator Charts for Profile Projector. Condition: Used. Listed at 49.99 USD. Rare TWA Trans World Airlines Optical Comparator Charts for Profile Projector Vintage Used Condition. I purchased these at an estate sale. Not sure exactly how they were used on the job. See all pictures as a couple plates have some defects. Some are plastic charts, and some are glass. See all pictures as they are part of the description. Comes in original box. If you have no interest in the protective box, I can sent the charts at a cheaper price. Optical Comparator Chart For Profile Projector Optical Comparator Chart Overlay Mylar Profile Projector Designed for use with profile projectors whose screen diameter is 300mm or larger.Protractor (1º-grad. radial index) and radius (1mm-radius increment concentric semicircles)package:1 Optical Comparator Chart. Shipping by way of USPS, FEDEX OR UPS AT $24.95. See Pictures as they are the best descriptions. Please let me know if you have any questions or need further information. See my other very nice items at my eBay Store SHMSTORELLC | eBay StoresInternational Buyers - Please Note: Use eBay Global Shipping Program Shipping to U.S. Territories outside the lower 48 States will have extra shipping cost.Thanks for looking.