Gammex RMI?, Middleton, Wis, offers the 469 IMRT Phantom, which gives simple, highly reliable dose validation of complex 3D treatment plans. Using Solid Water? construction, the compact device offers easy handling and accurate alignment. The phantom is enclosed in a light-tight cassette incorporating a locating pin to register the phantom with the CT or linear accelerator coordinate system and white scribe lines to ensure proper alignment. The phantom has provisions for an optional adaptor for a customer-specified cylindrical ion chamber. A blank plug is included if the use of an ion chamber is not desired. (800) 426-6391; .