1-203-402-0477 [email protected]


Download the free iOS or Android Apps now from Apple or Google Play app stores (search “WolfSense Mobile”).

AP-OW5 connected to DirectSense II

Check out the demo mode (with simulated readings) to get an idea of how the GrayWolf DirectSense® II probe can use your personal (or a dedicated) Android or Apple (iOS) smartphone/tablet as a simple display and/or advanced data-logging device. Follow the instructions when you open the app to access simulated readings.
Loads of features such as:

  • Display and log from 1, up to 3 probes simultaneously (up to 8 sensors in each probe)
  • Snap-Logs during walk-thrus and Trend-Logs over time
  • Attach photos, videos, audio and text right to your location/data files
  • Display detailed tabular data and simple graphs on your smartphone/tablet
  • Download readings to WolfSense PC software, provided at no charge, for elaborate graphs, data display and reporting
Many more features already available, with even more coming.

Choose Your Platform

Of course, GrayWolf’s highly feature rich AdvancedSense® Pro, AdvancedSense BE and Windows Tablet platforms ALSO work with the same DirectSense II probes; via wireless or via cable connection.

Configure a high-end, reliable GrayWolf system to meet your specific measurement needs, current and future.

Contact us with any questions or to schedule a demonstration (online, or in some areas, in-person). Call 1-203-402-0477, email [email protected] or fill out a request form for price quotes, rentals or local distributor information at

FP-31G Formaldehyde Meter

NEW: GrayWolf is now branding this portable HCHO meter with exceptional low limits of detection (LODs).

The FP-31G meter may be used from 10ppb to 1.0ppm and is ideal for IAQ applications (30-minute test) or low toxic exposures (15-minute test).
While this low formaldehyde detection meter does not continuously monitor or directly output to GrayWolf platforms, readings can be manually entered into WolfSense log files, at the time that they are taken, supplemental to a host of other GrayWolf continuous IAQ or toxic exposure parameters. GrayWolf has years of experience offering this meter, with proven performance, allowing us to now add our name (and the extra support that goes with that) to the product.

FM-801 Replacement Cartridges
A reminder that replacement Sensor Cartridges for our former HCHO product, the FM-801, are being discontinued. A final production run by the manufacturer is exclusively being run for GrayWolf end Nov/early Dec. These cartridges are sold singly (FM-ACC-C1), in lots of 5 (FM-ACC-C5) or in lots of 10 (FM-ACC-C10) and have a one-year shelf life from date of manufacture. For ongoing use of your FM-801* meters, order now from existing inventory, or preorder from the final production run. Once they are sold out, they will not be available from GrayWolf or elsewhere.

*There are literally just a few FM-801 remaining in inventory if you are interested in adding 1 for just over 1 year of use. They are supplied with 5 sensor cartridges each.


The new WolfRadio board, which enables Bluetooth Low Energy to communicate to Apple (iOS) and Android devices, cannot be added to DirectSense II probes manufactured prior to September 2021. However, GrayWolf is offering a generous trade-in program for you to swap your DSII probes for a new DSII probe with WolfRadio on-board.

You can reuse your smart sensors. Contact us for details on how to take advantage of interfacing both with your GrayWolf devices and with your own smartphones/tablets.

For Detailed Information: