WarmMark® Duo Time-Temperature Indicator

Model 51036

  • Accurate time/temperature monitor
  • Visual pass/fail confirmation of exposure to temperature excursions
  • Irreversible color change indicates length of time above thresholds
  • Calibrated to respond within ± 2°F/± 1°C
  • Low cost, easy to use
Applications: Shipping, Storage, Distribution of Vaccines, Pharmaceuticals and Blood Products


The WarmMark® Duo Time-Temperature Indicator is a single use label typically applied to vaccines, pharmaceuticals, and blood products for monitoring conditions during storage, shipping and distribution. It has two response temperatures indicating accumulated time above 50°F/10°C, and brief temperature excursions above 93°F/34°C.

WarmMark® Duo Time-Temperature Indicator, Model 51036, is a single-use thermal label designed to monitor temperature of blood and blood products, vaccines, and other pharmaceuticals during storage, shipping and distribution. It responds at two temperature thresholds, and is used for products with a known stability curve and with identified expiration characteristics for a specific time/temperature combination.

This cost-effective, self-adhesive label can be applied directly to a product and easily fits inside temperature-controlled packaging. When activated, the indicator windows remains white unless the label is exposed to temperatures above 50°F/10°C, then an irreversible red color migrates progressively towards the three windows. If the temperature goes below threshold, the color stops advancing. The first three windows indicate accumulated time above threshold, when colored red they denote exposure up to 3 days, 8 days, and 14 days. The fourth window indicates brief high temperature excursions, and turns red if the temperature goes above 93°F/34°C for at least 30 minutes.

WarmMark® Duo shows at a glance if temperature abuse has occurred and for how long, thus providing visual evidence for making immediate decisions on whether product safety, efficacy and quality have been jeopardized.

Model 51036 WarmMark® Duo Time-Temperature Indicator
DeltaTrak manufactures products under an ISO 9001:2015 registered quality management system
Activation Temperatures 50°F/10°C and 93°F/34°C
Exposure Time Period above 50°F/10°C Up to 3 days, 8 days, 14 days
Exposure Time Period above 93°F/34°C Within 30 minutes
Accuracy ± 2°F/± 1°C of response temperatures
Tag Size

3.88 x 0.75 x 0.06 in
(98.1 x 19 x 1.5 mm)

Adhesive Pressure sensitive
Storage Conditions Unused product must be stored below response temperatures and between 35-55% RH for optimal shelf life
Shelf Life Two years from date of sale
User Guide
User Instructions
Misc Info
  • DeltaTrak’s Real Time Loggers have been a game changer for our trucking program. Having the ability to monitor temperature while trucks are in transit has given us peace of mind knowing the quality of our product has not been compromised. The alert notifications, light sensors, and GPS tracking are just some of the great features that have allowed us to make pro active decisions that have strengthened the integrity of our product. The FlashTrak Cloud Service is easy to use and is a great tool to compare and analyze data. The FlashTrak App is super convenient as well. We have used other reliable DeltaTrak products for many years and we were excited to see these added to their lineup!

    Michelle Oetjens
    Senior Global Logistics Analyst-BFP
    Ball Horticultural Company

  • When it comes to making sense of data (in the supply chain) we have found a partner in DeltaTrak. The fact that I could recharge the real-time logger and the dual batteries made a lot of sense to me. It was user friendly and easy to use. With the uncertainty and complexity of today's supply chain, having an effective chain of custody system is not only a clever idea, but a requirement for effective handling of perishable goods.

    Henry Helms
    CH Logistics, Cape Town, South Africa

  • It is my pleasure to recommend DeltaTrak to your company. During these times of crisis, we were fortunate to work with DeltaTrak to source top of the line Non-Contact forehead thermometers and PPE supplies at a real market price.

    As a healthcare organization, we are a common target for price gouging and abusive practices from several vendors. With DeltaTrak, we found a partner that understands our needs and who always provide world class customer service.

    Luis Landgrave
    Procurement Manager
    Plum Healthcare Group LLC

  • Dear Fred, I would like express my appreciation for the good business relationship we have had during 2018. The excellent work of Mr. Jorge Hurtado has given me the confidence to continue maintaining our commercial relationship with the DeltaTrak brand.

    Mr. Jorge Hurtado's customer service efforts are outstanding, especially in finding solutions to the challenges that may arise in the commercial process. In my opinion Mr. Hurtado's professionalism is a model for any company, especially when the client is thousands of kilometers away from Modesto, CA. I look forward to strengthening our successful relationship into 2019.

    Valentin Bobadilla
    Valentin Bobadilla Centurion E.I.R.L.

  • We received the blankets yesterday and the quality was/is outstanding. Thank you for getting us a superior product, both our flowers and our customers thank you. :)

    Clint C.
    Aladdin's Floral

  • We have provided our trucks with your recorders for Walmart/Sam's and have not had any issues at all. Great recorders, small in size and easy to activate and place in the truck.

    Diego Calderon
    Delano Farms Company

  • Thank you Juan Solorzano for paying us a business call 4 years ago. The DeltaTrak brand is the majority of our Temp Recorder business. ALL our Walmart/Sam's orders carry the DeltaTrak Temp recorders for the past 4 years without a single problem with any Walmart DC. When you have a load of 18 different orders on a single truck and temp recorders on each order, WOW what a savings your DeltaTrak brand has save us. Yes, Walmart has accepted the DeltaTrak Model with no problems.

    Tony Contreras
    The Giumarra Companies, Reedley Cold Storage

  • This upcoming fall will mark our 4th full season using DeltaTrak recorders. They are competitively priced and the customer service is always exceptional. We have never had a customer issue with one of their units and we don’t expect to. We use a wide range of DeltaTrak products and we have been more than happy with every one of them.

    Bruce Densten
    Little Bear Produce