Free evaluation kit · 3 Pinktail indicators

Proof your samples stayed frozen, the moment you open the box.

Pinktail is a small indicator that ships inside the box, beside your vials. If the shipment warmed past your limit, it turns clear and stays clear. No data loggers, no downloads, no guessing.

Two Pinktail indicators side by side: one clear after a temperature excursion, one still pink
Pink: stayed within limit Clear: limit was exceeded
Pinktail evaluation 3-pack in a foil pouch
What you'll receive

The full evaluation kit, free

The same production-grade indicators used to monitor high-value biologics and vaccines, at the signal temperature you choose.

  • 3 ready-to-use Pinktail indicators
  • Activation guide
  • Reference card for reading each state
$0 No credit card. No obligation.
Why teams switch

Know what happened to every box

External labels tell you about the outside of the package. Pinktail tells you what your samples actually experienced.

A researcher places an activated pink Pinktail indicator into a cryobox beside an ultra-low freezer
Pinktail rides with your samples, placed right in the box before it ships.
  • Travels with the samples

    Sits directly on your vials or trays inside the box, so it sees what they see.

  • Deep-freeze ready

    Signal temperatures from −67 °C to 0 °C cover dry ice, ultra-low and standard cold-chain shipments.

  • Irreversible proof

    Once triggered the change is permanent, even if the box is refrozen before it reaches you.

How it works

Three steps, no training

Anyone on the receiving end can read it at a glance.

1
Activate

Twist the cap closed, then flick and shake until the base turns deep pink.

2
Place

Set it directly on your vials or trays inside the shipping box.

3
Verify

On arrival, check the base. Pink means safe. Clear means the limit was exceeded.

60-second demo

See Pinktail in action

Watch how easy it is to activate, place, and verify an indicator.

Specifications

Heat response at a glance

Indicators respond to cumulative heat exposure (time × temperature), not a single reading. Warmer means faster; colder means slower.

Ambient temperature Approx. time until clear
25 °C~15 min
4 °C~3 hours
Below signal temperatureNo change

Times shown are for the 0 °C indicator at the listed ambient temperatures.

Available signal temperatures
0 °C−18 °C−37 °C−67 °C
Indicator size

45.0 mm tall × 12.7 mm wide. Cap 12.7 mm dia., tube base 9.0 mm dia.

Fits a standard cryobox well or rides loose on dry ice.

Common questions

Before you request a kit

Short answers to the things people ask before they fill out the form.

Is the 3-pack really free?
Yes. Shipping is free too. We don't ask for a credit card, and requesting a kit doesn't commit you to anything. We simply want you to try Pinktail on a real shipment.
Who can request one?
Anyone who ships or receives temperature-sensitive samples at a lab, biobank, CRO, clinic or company. We ship to institutional and company addresses, which is why we ask for a work email.
What happens after I submit the form?
You'll get a confirmation email to confirm the shipping address. Your kit ships via FedEx within 2 business days, with tracking. No sales call is required.
Which signal temperature should I choose?
Pick the temperature your samples must stay below. 0 °C for refrigerated goods that must not warm, −18 °C for standard freezer shipments, −37 °C for deep freeze, and −67 °C for dry ice or ultra-low shipments. If you're unsure, choose "Not sure" and we'll recommend one based on your application.
Do I need any equipment or software?
No. Pinktail has no electronics, batteries or calibration. Activate it by hand, place it in the box, and read the result with your eyes on arrival.
Can a triggered indicator reset if the box is refrozen?
No. The color change is irreversible. Once the base turns clear it stays clear, so a breach can't be hidden by re-icing the package.

Stop guessing what happened in transit.

Put three Pinktail indicators on your next shipment and see for yourself. Free, shipped within 2 business days.

Request my free 3-pack → Takes about 30 seconds