The No-Rad Shields are computer screen overlays designed to eliminate glare and reflection, increase contrast, reduce static, and block 99.99 percent of E-field electromagnetic radiation transmitted through the face of video display terminals (VDT). Three models are available for a variety of computer monitors (each $139.95), and one model, the No-Rad Super Shield (R7440, $349) is designed for 19-inch monitors. COMPATIBILITY: Model R7428 can be used on the Apple IIC, Macintosh 128, 512, 512E, Plus, SE, and the Panasonic Sr. Partner. Model R7429 is designed for Amdek, AT&T PC 6300 Color, DEC VT, IBM, Princeton, Samsung, Taxan, Wyse, and Zenith computers. Model R7430 is made for use with Amdek, IBM, Leading Edge, Lear Siegler, Lee Data, Samsung, Sperry, Tandy, Taxan, Thompson, and Wyse computers. Contact manufacturer for specific models compatible with this product. DIMENSIONS: Model R7428 is 8.25 x 7 3/8 inches; model R7429 is 11 3/8 x 8 7/16 inches; and model R7430 is 12 3/8 x 9.5 inches.