Quality Inspection for 5.25 Foam Surround Repair Kit - 4″-Speaker Rubber Surround – EPDM Rubber Edge – Nandi Yanlong

The quality of the rubber edge has a great impact on the frequency response of the speaker, and the hardness directly affects the frequency of the speaker. The service life of rubber ring is also very long.

EPDM rubber surround has excellent resilience and is an ideal choice for outdoor speakers, gaskets and fasteners.

EPDM is a terpolymer of ethylene, propylene and non-conjugated dienes, which began commercial production in 1963. The annual consumption of the world is 800000 tons. The main characteristic of EPDM is its superior oxidation resistance, ozone resistance and corrosion resistance. As EPDM belongs to the polyolefin (PO) family, it has excellent vulcanization properties. Among all rubbers, EPDM has the lowest specific gravity and can absorb a large amount of fillers and oil without affecting the properties. Therefore, it can produce low-cost rubber compounds. EPDM is a terpolymer of ethylene, propylene and unconjugated dienes. Dienes have a special structure, and only one of the two bonds can be copolymerized. Unsaturated double bonds are mainly used as the crossing point. The other unsaturated chain will not become the main chain of the polymer, but the side chain. The main polymer chain of EPDM is completely saturated. This property makes EPDM resistant to heat, light, oxygen, especially ozone. EPDM is non-polar in nature, resistant to polar solutions and chemicals, low water absorption and good insulation characteristics.

Q1: Can you make OEM/ODM or custom order?
Answer 1: We welcome OEM/ODM or customized product list.

Q2: What is the packaging of your products?
Answer 2: The packaging method is based on the cartons uniformly used by the company, and special packaging will be charged separately.

Q3: Can I get samples from you for testing?
Answer 3: Customers are welcome to take samples for testing. Our company supports free samples of existing models. You only need to bear the freight.

Q4: What are the terms of payment?
Answer 4: 30% T/T deposit, 70% T/T balance payment before delivery. If there is special need, it can be negotiated.

Q5: Can I visit your factory?
Answer 5: 1. In the epidemic environment, our company provides remote online factory detection service. Please contact our business. 2. Welcome to visit the company for field inspection. Please make an appointment in advance before the investigation, so as not to delay your schedule.