DeFelsko PosiTest FM Gauge

DeFelsko PosiTest® FM Coating Thickness Gauge is a magnetic pull-off gauge for measurement of non-magnetic coatings on steel. Commonly referred to as a banana gauge, PosiTest® mechanical Coating Thickness gauge is explosion proof, making it safe for refinery use.

SKU: DEF-FM Category: Tags: , ,


DeFelsko PosiTest FM Coating Thickness Gauge is an easy-to-use magnetic pull-off gauge (banana gauge) for measuring cured coatings on steel. PosiTest is explosion proof, making it safe for use in refineries and similar applications.

The PosiTest Coating Thickness Gauge offers a dial indicator in mils or microns, with scales for thinner non-magnetic coatings like galvanizing, or thicker coatings up to 80 mils on steel. PosiTest features a rugged housing that is impact, water, acid, and solvent-resistant. V-grooves on the probe end permit measurement of coatings on cylindrical objects. PosiTest is lightweight and compact, and is balanced so that it works in any position.


  • Wear-resistant carbide probe for long life and continuous accuracy
  • Easy calibration adjustment
  • Housing not affected by mechanical shock, water, acid or solvents
  • Design ensures instrument stability for reliable readings
  • Explosion proof and refinery safe
  • Visual and audible indicators when reading is established
  • Compact, lightweight, precisely-balanced independent of gravity – can be used in any position
  • Go/no-go button can be preset for rapid measurement
  • One-finger operation

PosiTest is available in four scales:

  • PosiTest FM: 0 – 80 mils; tolerance of +/- 0.2 mils to 4 mils, +/- 5% of reading over 4 mils
  • PosiTest F: 0 – 2000 microns; tolerance of +/- 5 microns up to 100 microns, +/- 5% of reading over 100 microns
  • PosiTest GM: 0 – 8 mils; tolerance +/- .04 mils up to .8 mils, +/- 5% of reading over .8 mils
  • PosiTest G: 0 – 200 microns; tolerance +/- 1 micron up to 20 microns, +/- 5% of reading over 20 microns

Stone Tucker Instruments is able to recertify your DeFelsko PosiTest FM Coating Thickness Gauge, as well as all other brands of magnetic pull-off coating thickness gauges (banana gauges).

Weight1 lbs
Dimensions10 × 4 × 2 in

DeFelsko’s PosiTest FM Gauge comes with:

  • Wrist Strap
  • Neck Strap
  • Instructions
  • Leather Case

Click here to download the DeFelsko PosiTest FM Datasheet

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