The external shutter is designed to control the camera shutter underwater to take  pictures, video and even access third party photography apps by Bluetooth underwater

• Can be used both on Land and Underwater
• Multiple Installation options; can be installed direct to SeaTouch 4 housing or to a camera tray (fits the Dive Lantern CT25 and CT35 camera trays)
  
• Ultra-low Power Consumption Operation:
• Low-frequency operation sleep mode for power saving, automatically powers off after 10 minutes of inactivity
• Rigorously tested for longevity
  • Over 100,000 Keypress Tests
  • Withstands 60m Water Pressure
• Waterproof down to 200 FEET (60M).
• Compatible with Android and iPhone smartphones