This company is offering a free interactive Air System Maintenance CD that details common maintenance functions for rotary screw compressors, refrigerated and desiccant dryers, filters and drains. Using instructional video, voice over and graphics, this CD illustrates the steps necessary for routine maintenance and keeping air systems in top operating conditions. Included are Website links for many accessory products. This company also offers parts for preventive maintenance and repair of compressed-air equipment (photo, p. 56). — Kaeser Compressors Inc., Fredericksburg, Va.