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White 3M 5559 water contact indicator discs on tape roll

3M

3M 5559 Water Contact Indicator 2mm 5mil PK100

SKU CH-QTJ9-Z3273

Water-contact indicator discs turn red when wet, supplied as a pack of 100 with a 2 mm diameter and 5 mil thickness

  • Product typeCaulks
  • Instantly spots moisture with clear white-to-red colour change
  • 100 indicators per pack supply multiple inspection points
  • 3/32 in discs fit tight joints and narrow gaps
  • Operates reliably from -40 °F to 149 °F in harsh environments
  • Trusted 3M quality meets ASTM standards for consistent results

5559 Series Water Contact Indicators

These 3M indicators come in a pack of one hundred discs designed to reveal liquid exposure. Each disc measures two millimetres in diameter and turns from white to red on contact with water. They suit technicians who need a visual record of moisture ingress during assembly or inspection.

Sustained temperature performance

The tape carrier operates continuously from minus forty degrees Fahrenheit up to one hundred forty-nine degrees Fahrenheit. Adhesion and indicator chemistry remain stable across this range, so the discs do not release or false-trigger during prolonged thermal cycling. The five-mil thickness supports consistent behaviour over long dwell times.

Tape carrier limits

The carrier width is point zero seven inches and the total thickness is five mil, which sets the minimum surface area and curvature the disc can conform to. ASTM compliance confirms the material meets the referenced standard for this indicator type. Surfaces narrower than the tape width or radii tighter than the carrier allows will prevent full contact.

How it compares

Measured against everything we stock in Caulking & Sealing Supplies, at today’s prices. Recalculated every night.

Price $13.99
Cheaper than about 60% of the 631 comparable items (median $16.99).

Specifications

Product
Brand name3M
Product typeCaulks

Questions about this item

Does the indicator disc change colour after the tape has run continuously at 149 °F?

The indicator turns red only when liquid contacts it; the 149 °F figure is the tape's upper operating temperature, not a trigger for colour change.

What surface preparation or adhesive is required before applying the 0.07 in wide tape?

The tape is self-adhesive; ensure the surface is clean, dry and free of oil so the acrylic adhesive bonds properly.

Will the 3/32 in diameter discs still show a clear colour shift on a textured or curved panel?

The small disc conforms to moderate curves, but heavy texture can trap air underneath and reduce visibility of the white-to-red change.

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