Whether CE, DOP or ETA - we make sure that all the necessary certificates will be at your disposal on time and in accordance with the legal requirements.

  ITT (Initial Type Testing)

The Initial Type Test (ITT) to assess the production process is the prerequisite for the affixing of the CE marking performed by the building product manufacturer. The ITT has to be carried out by an accredited test center. The initial assessment is necessary for the determination of the product type and must be performed before the start of the series production of the construction product.


The European Technical Approval (ETA) certifies the technical fitness of a construction product as required by the EU Construction Products Directive. An ETA can be requested by the manufacturer on a voluntary basis if their construction product differs from those subjected to harmonized EU standards. The same applies for products for which no harmonized standards exist. AV24.jpg
A CE-Certification (in accordance with ETA) will be issued after a successful auditing and assessing of all the applied conditions carried out by the competent authorities.

DIN LING takes care of all the steps required for obtaining the CE-Certification.

  DOP (Declaration of Performance)

If a construction product conforms to the European Technical Assessment or is subjected to a harmonized European standard, then (according to the EU Construction Products Regulation) the product in question requires a declaration of performance (DOP). In the declaration of performance, the construction product manufacturer has to describe the main features of their product in detail.
Through the creation of the declaration of performance (formerly: Declaration of Conformity), the manufacturer confirms that the listed characteristics of the product corresponds to the declared performance.
The manufacturer also takes on the responsibility for this information. The declaration of performance serves as the basis for the subsequent CE marking of the product and must be kept for at least 10 years. Since 2014, the declaration of performance doesn’t have to be provided in printed form but can be made available to customers via the Internet too. As a special service, we generate the necessary declaration of performance for our customers upon request.


Under the Construction Products Regulation, the CE marking for fasteners became mandatory in July 2013. The products marked with CE have unhindered access to the European market or their contracting states. With a CE marking, the manufacturer confirms that they have carried out the prescribed method of verification. AV24.jpg



The AV24 seal proves the compliance with usual market conditions as well as with the common safety and quality standards. It also guarantees that the high quality standards of the audited fasteners even go beyond the minimum legal requirements for obtaining the CE marking.

While the external supervision of construction products with CE marking by notified bodies merely refers to processes, the AV24 Certificate goes one step further and checks your product and its properties. With the AV24 Seal you guarantee your customers and business partners a proven, continuously high quality of your marketed screws. You also boost their confidence in your product. You benefit from the appreciation of your unique product and you stand out from competitors. With our competent support you will gain a significant competitive advantage.

DingLing Group

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