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Q Can I have my box design and put my logo on the products?
A Yes, sure. we can customize the box and put your logo according to your design for your order.
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Q Do you have quality system?
A Yes, we have. We have set up our quality system and well controlled our production quality as per the instructions and requirements in it and well-control each procedure throughout the mass-production.
①To ensure the material component follows the ASTM standard, D&D use spectrometer to check the stainless steel raw material before production.
②D&D use measuring tools to check the product in each procedure throughout the mass-production to ensure the dimension of product meet customer’s requirement.
③ D&D arrange Quality control department in each step of the mass-production to ensure each production fulfill their duty to produce well-product.
④D&D use salt spray testing machine to test the product, to ensure it meet specific corrosion-resistance requirement.
⑤ D&D test products on testing machine very often to ensure products meeting CE / UL / ANSI standard.
⑥ D&D use 2D and 3D drawing to communicate with customer, which is clearly and accurately.
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Q What's your main market?
A We has established long business relations with customers from Europe, Middle East , America and Asia, benefit from quality assurance, expertise knowledge ,competitive pricing, customization ability and great service.
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Q What certificate you have?
A We have CE，UL and ANSI/BHMA cerfificate, all our product design follow up the international standard（European Standards& American Standards）, such as the EN/CE, UL, ANSI standard. Suitable for education, healthcare, hospitality, residential and commercial applications.
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Q A Word On ANSI/BHMA A156.4
A ANSI/BHMA A156.4 is the American national standard for the mechanical performance of door closers — cycle life, closing force, backcheck and finish are graded from Grade 3 up to Grade 1, with Grade 1 the most demanding. It complements rather than replaces a fire listing: UL 10C addresses how the closer behaves in a fire, while A156.4 addresses how it performs over years of daily use.
D&D's closers are UL listed under File R40717. Where your project specification also references ANSI/BHMA A156.4 grades, tell us the required grade and duty cycle and we will match the right model from our range — understanding both standards helps you specify the right closer the first time.
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Q Do you ship globally, and what documents come with the shipment?
A We export regularly to North America, the Middle East and Southeast Asia. Shipments carry commercial documents plus the UL certificate details (File R40717) so your team can present listing evidence at inspection.
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Q What is the lead time and MOQ for bulk orders?
A Stock models ship within days; production orders typically run 30–45 days depending on model, function and finish. MOQ varies by model — send your door schedule and we will quote quantity breaks together with the inquiry.
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Q Can I get OEM or custom logo on UL certified closers?
A Yes. We support custom logo, color and packaging on listed models. The UL mark and label stay exactly as listed — OEM branding is applied without affecting the certification.
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Q Which D&D door closer models are UL certified?
A 67 models are listed under File No. R40717, from DDDC005UL to DDDC067, including BC and DA variants such as DDDC016BC and DDDC060DA. The full list is printed on this page and can be cross-checked on the UL Online Certifications Directory.
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Q How long is the fire rating of D&D UL door closers?
A The listing covers swinging type fire doors rated up to and including 3 hours. The rating that applies to your opening depends on the door assembly specification — always match the closer label to the rating required by the door schedule.
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Q What does a UL 10C fire rating mean for a door closer?
A UL 10C is the positive-pressure fire test for door assemblies used across North America. Our closers were tested as part of swinging fire door assemblies and held the opening for up to and including 3 hours, as stated on Certificate No. 20251103-R40717.
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Q Can D&D support master-key or construction-key planning?
A D&D’s BS EN 1303 cylinder category identifies master-key suites and construction-key options as available key-management approaches. Availability and architecture should be confirmed against the selected cylinder series and the project’s access hierarchy. Include the number of doors, user groups and temporary-access needs when you send the brief.
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Q Does the 183-minute EN 1634 statement apply to every cylinder size and door type?
A The stated 183-minute EN 1634 performance must be verified against the applicable test or certification record for the intended configuration. This page intentionally does not treat a time result as a blanket claim for every length, function, lockcase or door build. Request the evidence pack for the specific cylinder and fire-door assembly you are planning.
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Q Is BS EN1303 mandatory for European projects?
A Yes, BS EN1303 is the required standard for euro profile cylinders in most EU and UK building regulations. Our cylinders pass 100,000 cycle tests.
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Q What does EN1634 fire rating mean?
A EN1634 certifies the cylinder can withstand fire for 183 minutes, meeting European fire door safety standards for commercial and public buildings.
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Q What does “EN fire rated lock cylinder” mean for a fire door project?
A It means the cylinder should be evaluated as part of the proposed fire-door hardware set, not selected only by profile or finish. Ask for the performance documentation that applies to the exact cylinder configuration, lockcase, door construction and test scope being considered. A matching profile by itself is not proof that every combination has the same fire-performance result.
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Q How do I get a quotation?
A Email sales@danddhardware.com or message +86 139 2903 7292 on WhatsApp with your door types, target certification (UL or EN), load requirements and estimated quantities. Our sales engineers respond with a tailored quotation, datasheets and certification documents within 24 hours on business days.
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Q Do you support OEM/ODM? What are the MOQ, sample and lead times?
A Yes — OEM/ODM is core to our business. Choose from finishes including satin nickel, matt black, PVD, antique brass and antique copper, or specify custom load ratings, branding and packaging. Typical MOQ is 200–500 pieces, samples ship in 5–7 working days, production takes 30–35 days, and monthly capacity is 200,000 units.
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Q What is a hydraulic concealed hinge and where should I use it?
A A hydraulic concealed hinge integrates a damped self-closing mechanism inside the hinge body, replacing a visible overhead door closer. Our DDCHSL613 supports doors up to 60kg and 900mm wide, opens to 180° and offers adjustable closing speed. It is ideal for hotel rooms, hospitals, offices and residential invisible doors where silent, automatic closing matters.
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Q What load capacities are available for the certified models?
A The DDCH008 is available in 40kg, 80kg and 120kg load ratings; the DDCH011 comes in 60kg and 100kg versions. Final capacity depends on door dimensions, weight distribution and the number of hinges per leaf — send us your door schedule and our engineers will recommend the correct configuration.
