The SM-6, made by SENSOR Nederland, is a vertical geophone in a PE-5 case, and with a 75 mm steel spike. The geophone string consists of six geophones spacing 10 metres each, with a lead-in of two metres, and terminated with a PE-7 multiple string connector with wide and narrow clips.

Pool Contents
Geophone String                         300 Units: 4.5 Hz

Mechanical Parameters
Sensor                                             6 * 1 vertical geophone

Signal Output
Sensitivity                                     27.5 Vs/m (single geophone)
Response                                       Ground velocity from 4.5 Hz to > 150 Hz
Damping                                        0.71 (4.5 Hz type)

Physical Parameters
Weight                                            Complete Chain: 3 kg (incl. carry hasp)
Operating Temperatures      - 40 to +100 °C