This is a vintage letter from a California company specializing in "Smith-Precision Crystals - Manufacturer of Fine Quality Piezo Electric Quartz Plates," and is dated Sept 13 (no year indicated but is 1930s/early 1940s vintage). Condition: All radio related paper items offered have scattered handling wear, creases etc. Please see scan and contact me with any questions. See my listings for a large selection of vintage radio related paper items (regarding crystals, radio station letterhead, correspondence, etc), as well as other unusual, interesting and fun vintage items. Multiple purchases are combined with a single postage charge. All items are shipped sleeved in plastic, and packaged between sturdy cardboard.