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Defelsko - PosiPen - Magnetic Pull-off Coating Thickness Gage

Defelsko - PosiPen - Magnetic Pull-off Coating Thickness Gage

Starting at $265.00
PosiPen has a very small, unique magnet which can be placed with pin-point accuracy on extremely small parts, and on peaks and valleys. Ideal for measuring non-magnetic coatings such as paint, enamel, plating, and hot-dip galvanizing on steel.
  • Can be used on small, hot or hard-to-reach surfaces
  • Range: .00025" - .002" (.25 - 20 mils)
  • Easy-to-Use
  • Lightweight—easy to carry, just like a ball point pen
  • Rugged—not affected by mechanical shock, acid, oil, water and dust
  • No user adjustment required
  • Highly wear resistant probe tip for long life and continuous accuracy
  • Certificate of Calibration showing traceability to PTB included (Long Form)
  • Conforms to ASTM D7091/B499, ISO 2808 and others
Additional Information +
Item No. Our Price QTY
PEN $265.00




1. Place the tip of the PosiPen on the coated surface and allow the magnet to contact.
2. Pull the PosiPen straight back from the object to be measured while keeping close watch on the appropriate indicator.
3. Note the reading when the magnet releases.
can be used on small, hot or hard to reach surfaces
Can be used on small, hot or hard-to-reach surfaces


Triple Indicator Compensates for Gravity

The PosiPen compensates for gravity when measuring in different positions.

  • Use the red/silver joining line when the Gage is horizontal (walls). 
  • Use the green line when the Gage is pointing straight down (green/ground). 
  • Use the blue line when the Gage is pointing straight up (blue/sky).

Is the PosiPen calibrated at the factory?

The PosiPen arrives fully calibrated and ready to measure. A Long-Form Certificate of Calibration traceable to NIST or PTB is included, which documents actual readings taken by your instrument at our calibration laboratory on standards traceable to a national metrology institute. Beware of ‘Certificates’ or ‘Certificates of Conformance’ offered by competitors. These typically do not include actual instrument readings, and are often insufficient to meet common quality requirements.

Why should I purchase the PosiPen instead of the PosiTest?

The PosiPen is ideal for measuring non-magnetic coating thickness with pinpoint accuracy on ferrous metal parts with temperatures ranging from -100C to +230C (-150F to +450F). The PosiPen uses a very small magnet can be precisely placed on extremely small parts and on coated surfaces which cannot be accessed by other, larger gages.

Is the PosiPen affected by the roughness of the steel substrate below the coating?

All coating thickness gages are influenced to some degree by substrate roughness. It is generally accepted that coating thickness should be measured from the highest ‘peaks’ in the rough surface thus ensuring they are covered by the protective coating. However, coating thickness gages will instead measure the coating thickness from the effective magnetic surface, which is located somewhere between the highest peaks and deepest valleys of the profile.

To compensate for the influence of substrate conditions (including roughness), measure the uncoated substrate/part at a number of spots to obtain a representative average value. This average value is called the “base metal reading” or “BMR”. Subtract the BMR from subsequent coating thickness measurements to obtain the thickness of the coating over the ‘peaks’ of the rough surface.

Yes. The PosiPen will accurately measure the thickness of non-magnetic coatings on a ferrous 18 AWG and larger wire.

Can the PosiPen measure nickel on steel?

Yes, but it depends upon the particular type of nickel coating that has been applied to the steel.

When nickel plating is deposited by a process of electrolysis (employing an electric current in the nickel bath), the resultant coating – commonly called “e-nickel” – is always conductive and magnetic to some degree and cannot be accurately measured by our gages when applied to ferrous or non-ferrous metals.

Electroless nickel coatings are deposited by an autocatalytic process which does not involve the addition of an electric current. If the nickel bath in this process contains a minimum concentration of ~8% phosphorus, the resulting nickel plating is effectively non-magnetic and its thickness can be accurately measured on ferrous steel with a magnetic principle coating thickness gage such as the PosiPen.

Does the PosiPen measure on non-ferrous metals, like aluminum?

No. As a magnetic principle instrument, the PosiPen will measure the thickness of non-magnetic coatings applied to ferrous metals. Our popular PosiTest DFT Combo and powerful PosiTector 6000 N gage models are ideal for measuring the thickness of paint, anodize and other non-conductive coatings applied to non-ferrous metals.

Can the PosiPen be adjusted?

No. The PosiPen uses a precision, permanently- calibrated spring which will never require adjustment.