Abstract: An acceleration-sensing mass/magnet is positioned about the center activation region of a reed switch. Motion of the acceleration-sensing magnet in either direction along the reed switch causes the reed switch to close. A first mechanism for sensing shock in a first direction is contained between a flange and a lid connected by a cylindrical wall. The flange and lid ride a plastic tube that contains the reed switch. The acceleration-sensing magnet travels between the flange and the lid on the tube. A second mechanism for sensing shock in a second opposed direction is formed by positioning a second mechanism about the magnet and the first mechanism. The second mechanism for sensing shock has a spring that biases the lid of the plastic sleeve against an abutment formed by a portion of a plastic capsule that encloses the entire shock sensor.