5/12/05 DRS Technologies Inc. S-4/A 1:232K Toppan Merrill-FA DRS Codem Systems, Inc. DRS Communications Co. LLC DRS Data & Imaging Systems Inc. DRS Electric Power Technologies Inc. DRS Electronic Systems Inc. DRS Engineering Development Labs Inc. DRS Ew & Network Systems Inc. DRS Fpa Inc. DRS Infrared Technologies LP DRS International Inc. DRS Optronics Inc. DRS Power & Control Technologies Inc. DRS Power Technology Inc. DRS Sensors & Targeting Systems Inc. DRS Signal Recording Technologies Inc. DRS Signal Solutions Inc. DRS Signal Technologies Inc. DRS Surveillance Support Systems Inc. DRS Systems Inc. DRS Systems Management Corp. DRS Tactical Systems Inc. DRS Technical Services Inc. DRS Technologies Canada Inc. DRS Test & Energy Management Inc. DRS Training & Control Systems Inc. DRS Unmanned Technologies Inc. Integrated Defense Technologies Inc. Nai Technologies Inc. Night Vision Equipment Co., Inc. Paravant Inc. Tech Sym Corp. 4/7/05 DRS Engineering Dev Labs Inc. S-4 10:935K Toppan Merrill-FA DRS Communications Co. LLC DRS Data & Imaging Systems Inc. DRS Electric Power Technologies Inc. DRS Electronic Systems Inc. DRS Ew & Network Systems Inc. DRS Fpa Inc. DRS Infrared Technologies LP DRS International Inc. DRS Optronics Inc. DRS Power & Control Technologies Inc. DRS Power Technology Inc. DRS Sensors & Targeting Systems Inc. DRS Signal Recording Technologies Inc. DRS Signal Solutions Inc. DRS Signal Technologies Inc. DRS Surveillance Support Systems Inc. DRS Systems Inc. DRS Systems Management Corp. DRS Tactical Systems Inc. DRS Technical Services Inc. DRS Technologies Canada Inc. DRS Technologies Inc. DRS Test & Energy Management Inc. DRS Training & Control Systems Inc. DRS Unmanned Technologies Inc. Integrated Defense Technologies Inc. Nai Technologies Inc. Night Vision Equipment Co., Inc. Paravant Inc. Tech Sym Corp. 2/2/04 Nai Technologies Inc. S-4 13:2.5M Toppan Merrill-FA DRS Broadcast Technology Inc. DRS Communications Co. LLC DRS Data & Imaging Systems Inc. DRS Electric Power Technologies Inc. DRS Electronic Systems Inc. DRS Engineering Development Labs Inc. DRS Ew & Network Systems Inc. DRS Fpa Inc. DRS Infrared Technologies LP DRS International Inc. DRS Newco III Inc. DRS Nytech Imaging Systems Inc. DRS Optronics Inc. DRS Power & Control Technologies Inc. DRS Power Technology Inc. DRS Sensors & Targeting Systems Inc. DRS Signal Recording Technologies Inc. DRS Signal Solutions Inc. DRS Signal Technologies Inc. DRS Surveillance Support Systems Inc. DRS Systems Inc. DRS Systems Management Corp. DRS Tactical Systems Inc. DRS Tactical Systems West Inc. DRS Technical Services Inc. DRS Technologies Canada Inc. DRS Technologies Inc. DRS Test & Energy Management Inc. DRS Training & Control Systems Inc. DRS Unmanned Technologies Inc. Enterprise Electronics Corp. Integrated Defense Technologies Inc. Paravant Inc.