The world’s leading, smallest, and lightest handheld radiation detector

The R400 is a logical next generation instrument greatly based on the original identiFINDER. With 15,000+ identiFINDERs deployed worldwide inputs on how to improve this already excellent instrument have been few but valuable. The R400 is the result of taking these inputs and suggestions and adding them to the original instrument. The R400 uses the same algorithms that have proved themselves over many years of superb operation. The housing and three button, one hand operation is also the same. Following is a listing of the features added to make up the R400:

  • Extended 5 year service interval
  • Improved communications with industry standard Bluetooth and USB connections
  • New transflective color display, viewable in all lighting conditions
  • Storage for 600,000 spectra and GPS for location recording
  • No proprietary software used, simplifying customizing instrument settings and downloading industry standard n42.42 files.

The R400 is able to rapidly detect, quickly locate, accurately measure and precisely identify gamma emitting radionuclides.

The ability to detect gamma sources as well as the presence of neutrons in the radiation field via an optional neutron detector enhances the identiFINDERs capability.

The standard R400 includes a 1.4” (35 mm) diameter x 2” (51 mm) long NaI (Tl) detector plus a GM tube for high gamma dose rate measurements. Instruments are supplied with a carrying holster plus a wrist strap, serial cable, battery pack for rechargeable and non-rechargeable batteries, charging unit and a carrying case with shoulder strap. An optional, sealed 3He neutron detector can be added for neutron detection. The identiFINDER R400 is also available in fully submersible housing. Variations in operating conditions can affect the performance of radio-isotope identification devices (RIID) with scintillation detectors. Changes in temperatures or high count rates can cause measurements to shift impacting the peak positions and the instrument’s ability to ID accurately. The R400 automatically corrects for these changes by calibrating at start up and continuously stabilizing the measure through the use of an small internal source or our patented LED stabilization technique.

  • Customs / Border Security
  • First Responders
  • Civil Defense
  • Military / Law Enforcement
  • Nuclear Fuel Cycle/ Environmental
  • Steel / Scrap Metal Certification
  • Nuclear Medicine
  • Clear and readable display in all light conditions
  • GPS provides accurate location information
  • Reachback feature provides convenient access to gamma spectroscpist
  • Designed to meet ANSI N42.34
  • Detects, locates, measures and identifies radionuclides
  • Automatic calibration and continuous stabilization
  • Digital signal processing enhances data throughput
  • Easy, three button, one hand operation
  • Visible, audible and tactile alarms


Specifications relevant for certain variants only are labeled with the variant.


Gamma NaI *(A, B, C, D, E, F, G, H, I, J, K, M) Crystal size 35mm (1.38in) × 51mm (2.01in)
Gamma NaI *(L) Crystal size 23mm (0.91in) × 21mm (0.83in); tungsten shielded
Neutron 3He Proportional Counter Tube *(B, D, F, I, K) 15mm (0.59in) × 54mm (2.13in); net: 14mm (0.55in) × 29mm (1.14in); 8atm (8.106bar)
Gamma (High Dose Rate) Geiger-Müller detector
GPS 12-channel SiRF III receiver


Internal Source *(A, B, H, I, L) 137Cs; 15nCi (555Bq); Startup time: ≈60s
Internal Source *(C, D, J, K) 137Cs; 3nCi (111Bq); Startup time: ≈200s
External Source *(E, F, G, M) 40K; Startup time: ≈320s


Energy Range (Gamma) 20keV – 3MeV
Throughput >150kcps
Max. Input Count Rate 300kcps
Sensitivity (137Cs) >500cps per µSv/h
Corrections Real-time linearization of gamma spectrum
Gamma Spectrum 1024channels; 3MeV
Dose Rate Range 0.000µSv/h – 10.00mSv/h
dto. Scintillator 0.000µSv/h – 500µSv/h
dto. Geiger-Müller Detector 100µSv/h – 10mSv/h
dto. Overload 10mSv/h – 1Sv/h
Dose Range 0.000µSv – 1Sv
Neutron Sensitivity *(B, D, F) 2.6cps/nv
Stabilization *(A, B, H, I) Calibration source; ±1% for temperature change rate of
Stabilization *(C, D, J, K, L) Calibration source; LED; ±1% for temperature change rate of
Stabilization *(E, F, G, M) LED; ±1% for temperature change rate of
Nuclide Identification According to ANSI N42.34
Typical Resolution *(A, B, C, D, E, F, G, H, I, J, K, L, M) ≤8% FWHM at 662keV at 20°C (68°F) ambient temperature
Typical Resolution *(N) ≤6% FWHM at 662keV at 20°C (68°F) ambient temperature
Nuclide Library *(A, B, C, D, E, F, H, I, J, K, L, N) Standard library
Nuclide Library *(G, M) Environmental library


Recommended Interval 5a
Dimensions (W × D × H) *(A, B, C, D, E, F, G, L) 248mm (9.76in) × 93mm (3.66in) × 75mm (2.95in)
Dimensions (W × D × H) *(H, I, J, K, M) 270mm (10.63in) × 93.5mm (3.68in) × 82mm (3.23in)
Weight *(A, C, E, G) 1180g (41.62oz) including batteries
Weight *(B, D, F) 1200g (42.33oz) including batteries
Weight *(H, J, M) 1360g (47.97oz) including batteries
Weight *(I, K) 1380g (48.68oz) including batteries
Weight *(L) 1450g (51.15oz) including batteries
Housing Material Aluminium


Operating Temperature -20°C – +55°C (-4°F – +131°F)
Storage Temperature +10°C – +35°C (+50°F – +95°F)
Temperature Change Sudden temperature change must not exceed 30.0°C (54.0°F) in order to avoid damage to the detector crystal
Relative Humidity *(A, B, C, D, E, F, G, L, N) 10% – 80%, non condensing
Shock Resistance According to ANSI N42.34
Protection Rating *(A, B, C, D, E, F, G, L, N) IP53 according to IEC 60529; (with rubber cover mounted on socket)
Protection Rating *(H, I, J, K, M) IP68 according to IEC 60529; 10m (32.81ft); 8h


Type FLIR powerPACK ultra 2 (LSD NiMH, rechargeable)
Capacity >2000mAh; 4.8V
Operating Duration ≥8h at 20°C (68°F) in dose rate mode with dimmed display back light and GPS switched off
Charging Duration ≤4h at 20°C (68°F) when instrument off and connected to DC power charger and >4h when powered via USB.
Quiescent Current 16.5µA typically


Type Transflective color LCD
Size 68.4mm (2.69in); 320pixel × 240pixel
Central Luminance 400cd/m² typically
Blue LED *(B, D, F, I, K) Neutron detection and alarm
Red LED Gamma alarm
Amber LED Charging batteries
Green LED External power
Vibrator Alarm reporting
Beeper Keyboard feedback and alarm reporting
Data Storage Capacity 2GB internal memory; 1800MB available for the user
Identifications incl. Spectrum ≈600000
Data Logging Every 5s *(A, C, E, G, H, J, L, M) ≈5years
Data Logging Every 5s *(B, D, F, I, K, N) ≈2.5years
Screenshots ≈2500
Alarms ≈1000000
USB *(A, B, C, D, E, F, G, L, N) USB 2.0; micro-B socket
USB *(H, I, J, K, M) USB 2.0; LEMO Series K socket with bung
Bluetooth Class 2.0; ≤10m (32.81ft) range
Embedded Software Microsoft Windows CE Operating System
Web Interface TCP/IP emulated via USB
Download File Formats ANSI N42.42 and spc files compatible with third-party analysis software applications such as GADRAS, Cambio, or PeakEasy
Reachback ANSI N42.42 data via Bluetooth to DUN compatible cell phone
STRIDE Data Protocol STRIDE Data Protocol for network integration
DC Power Adapter, Charger AC in: 110V – 230V; 50Hz – 60Hz; DC out: 5V; 2A
Replacement Battery FLIR powerPACK 2 for 4 AA batteries
Connection Cable *(A, B, C, D, E, F, G, L, N) Micro USB-B – USB-A
Connection Cable *(H, I, J, K, M) LEMO Series K connector – USB A
Holster *(A, B, C, D, E, F, G, L, N) 210g (7.41oz)
Holster *(H, I, J, K, M) 220g (7.76oz)
Carrying Case Included
40K Source *(E, F, G, M) Box with potassium chloride (KCl)
Environmental Kit *(G) Smear pad holder; smear pads; disposable gloves; report stationery pad
ANSI N42.34 Performance Criteria for Hand-Held Instruments for the Detection and Identification of Radionuclides
IEC 60529 Degrees of Protection Provided by Enclosures (IP Code)
UL 61010-1, Part 1 Safety Requirements for Electrical Equipment for Measurement, Control, and Laboratory Use, 2005
EMC - Directive 2004/108/EC Regulations concerning electromagnetic compatibility
ANSI N42.42 2006 Data format standard for radiation detectors used for Homeland Security




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