T0, T1 and T2 Samples: Differences and Approval Criteria

During custom small appliance development, buyers may receive T0, T1 or T2 samples after the production molds are completed. These names describe different mold-trial rounds, but they do not automatically indicate that a sample has passed inspection.

The important question is not simply whether a sample is called T0, T1 or T2. It is whether the issues found in the previous round have been corrected and whether the product meets the agreed approval criteria.

At Chaozhou Tongheng Technology Co., Ltd., these samples are used to control mold correction, product verification and production approval for products such as portable fans, desktop fans, humidifiers and aroma diffusers.

For an introduction to the first formal mold trial, read What Is a T0 Sample in Plastic Injection Molding?.

T0, T1 and T2 at a Glance

The exact naming practice may vary between manufacturers and projects. Some products can be approved after T1, while others may require T2 or an additional trial. Reaching T2 does not automatically mean that the product is ready for mass production.

T0: Identify and Record the Problems

T0 is the first set of parts produced from the formal production mold. Its main purpose is to reveal actual molding, dimensional and assembly issues.

Typical checks include mold filling, flash, warpage, sink marks, key dimensions, housing fit, component assembly, visible gaps and basic product operation.

The normal T0 decision is not “approved for production.” It is confirmation of:

• The issues that must be corrected

• The parts or mold areas involved

• The proposed correction method

• The items that must be checked again at T1

If the buyer wants to change an already approved shape, dimension or function at this stage, it should be identified separately as a new design change rather than a normal T0 correction.

T1: Verify the First Corrections

T1 is produced after the agreed T0 corrections have been completed. The review should focus on whether each recorded issue has been solved.

The factory and buyer should check whether:

• Each T0 issue is closed, improved or still requires correction

• Molded parts, appearance, fit, assembly and functions meet the agreed requirements

• The corrections have created any new problems

If T1 meets the agreed criteria, the project may move into final verification and production preparation without a separate T2 trial. If important issues remain, another correction and sample round will be required.

T2: Complete the Final Recheck

T2 is normally used when issues remain after T1 or when the project requires another formal verification before production approval.

The factory and buyer should confirm that:

• Remaining T1 issues have been closed

• The corrected parts and final assembly match the approved specification

• Material, color, logo and surface finish are correct when included in the sample scope

• Product functions and required tests meet the agreed criteria

• No new critical issue has appeared after the latest correction

A T2 sample only becomes an approved production reference after the buyer and manufacturer complete the required review. The name “T2” alone does not make it a golden sample.

Sample Approval Criteria

The approval standard should be based on the confirmed product specification rather than a general impression that the sample “looks acceptable.”

Approval details should reflect the product. A portable fan may require checks for blade clearance, airflow, noise, charging and speed control, while a humidifier may require checks for sealing, atomization and water-shortage protection.

Three Possible Approval Results

“Conditionally approved” should not be used for unresolved safety, functional or critical assembly problems.

A Simple Sample Review Form

Buyers can use the following format when reviewing T0, T1 or T2 samples:

Clear feedback is more useful than comments such as “please improve the sample.” Mark the location, describe the issue and state the expected result whenever possible.

When Can the Project Move to Mass Production?

Before mass production begins, the following items should normally be confirmed:

For a clearly defined project, the T1/T2 optimization and production-verification stage normally takes approximately 15 working days. The actual time depends on the correction scope, test results, material availability and buyer feedback speed.

For the complete sequence from product definition to production, see OEM Product Development Timeline to Production.

Common Questions

Does every project require T0, T1 and T2?

No. A project may pass after T1, while another may require T2 or an additional trial. The result determines the number of rounds.

Can T2 be used as the golden sample?

Yes, if it meets the agreed criteria and is formally confirmed by both parties. Unresolved issues must be closed first.

Can the buyer request new design changes during T1 or T2?

Yes, but changes to an approved appearance, dimension or function may add engineering work, mold cost and lead time. They should be separated from manufacturing corrections.

Approve the Result, Not Just the Sample Name

T0, T1 and T2 provide a controlled method for finding problems, verifying corrections and preparing a custom small appliance for production. The number on the sample is only a record of the trial round.

Production approval should be based on closed issues, confirmed functions, acceptable appearance, stable assembly and aligned production documents. This reduces misunderstandings and helps both buyer and manufacturer move toward mass production with a clear standard.

If you are developing a custom fan, humidifier, aroma diffuser or another small appliance, contact Chaozhou Tongheng Technology Co., Ltd. and share your product brief, reference sample or current development status.