Regarding your request this is the main companies involve in the accelerometer market : Kistler (USA) Allied Signal (USA) Endevco (USA) VTI (Breed Technologies) (Finland) CSEM (Switzerland) Analog Devices (USA) Entran (France) Sensorex (USA) Lucas Varity (UK, USA ?) Sextant Avionique (France) PCB : I don't know the name precisely. All these companies have a Web site on wich you'll find informations about micro-machined accelerometer. All the Best !! Eric mailto:bonnotte@clamart.srpc.slb.com ===================================================== Eric Bonnotte Schlumberger Wireline and Testing SRPC- Clamart 26 rue de la cavee 92140 Clamart FRANCE Tel : +33 (0)1 45 37 22 95 Fax : +33 (0)1 45 37 26 93 =======================================================