bought this brand new a couple of months back for 200, used it 2 - 3 times, surplus to requirements - 150 posted.
has different colour palettes to choose from, To improve the detail level in thermal images, the ONE uses FLIR MSX technology to actively blend together thermal and digital images.
has its own chargeable independent power supply from USB, so does not use up your phone battery.

collection Wokingham - RG40 area, take J3 from M3 or J10 from M4 if you want to view it before purchase

FLIR ONE For iOS Key Features
  • Non-contact temperature measurements
  • 160 x 120 pixel thermal resolution
  • Turns iOS-powered devices into thermal cameras
  • FLIR MSX technology blends together thermal and digital images to improve detail
  • Built-in battery source won't drain your device's battery
  • Protective case included
  • FLIR ONE app - features include thermal panoramas, timelapse and more
  • Dongle design - plugs directly into phone/tablet connector
  • Temperature range of -4 to 248F (-20 to 120C)
  • Compatible with: iPhone 6, iPhone 6 Plus, iPhone 5, iPhone 5s, iPad Air, iPad Air 2, iPad Mini, iPad Mini 3 and iPad (4th generation)

photo of my son using this device, some nice detail for the price.
will consider swapping part-x for a semi auto 12g shotgun

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