Single Geophone in Vertical Direction, terminated with Split Spring Clip or Mueller Clips ( optional). With Geophone Types available as follows:

Single Geohone 1Hz in Vertical Direction

Single Geophone 2Hz in Vertical Direction

Single Geophone 2.5Hz in Vertical Direction

Single Geophone 3Hz in Vertical Direction

Single Geophone 4Hz in Vertical Direction

Single Geophone 4.5Hz in Vertical Direction

Single Geophone 8Hz in Vertical Direction

Single Geophone 10Hz in Vertical Direction

Single Geophone 14Hz in Vertical Direction 

Single Geophone 15Hz in Vertical Direction

Single Geophone 28Hz in Vertical Direction

Single Geophone 30Hz in Vertical Direction

Single Geophone 38Hz in Vertical Direction

Single Geophone 40Hz in Vertical Direction

Single Geophone 60Hz in Vertical Direction

Single Geophone 80Hz in Vertical Direction

Single Geophone 100Hz in Vertical Direction 

All the geophones are equipped in Waterproof Land Case with Steel Soil Spike and 1Meter Leader Cable and Terminated with Split Spring Clip or Mueller Clips.
Specification for SM24 Equivalent Geophone :

Natural Frequency (Hz): 10 ± 2.5%

Coil Resistance(Ω): 375 ± 2.5%

Typical Open Circuit Damping: 0.25

Damping Calibration-Shunt resistance(Ω): 1339 Ω

Damping with Calibration-Shunt : 0.6 + 5%, - 0%

Sensitivity: 28.8 v/m/s ± 2.5%

Sensitivity with Shunt Resistance (v/m/s): 22.50 v/m/s ± 2.5%

Harmonic Distortion (%): ＜0.1%

Typical Spurious Frequency ( Hz ):﹥240 Hz

Moving Mass (g): 11 g

Max Coil Excursion p-p (mm): 2 mm

Max Tilt Angle: 10o

Operating Temperature Range (℃): -45℃ To + 100℃