Q: What certifications do your spark plugs have?
A: All CORINTH spark plugs are manufactured in facilities certified to IATF 16949 (the global automotive-specific quality management standard) and ISO 9001 for general quality assurance. Full production is strictly aligned with ISO 11565 international spark plug performance standards and ISO 28741 dimensional interchangeability specifications, ensuring OE-equivalent quality, fitment and interchangeability.For customers targeting European and EMEA markets, E-MARK certification is available upon request for eligible models. Every wholesale shipment comes with complete batch traceability documentation, including raw material certificates and production test reports, to support smooth customs clearance and third-party quality audits.
Q: Do you provide OEM / private label service?
A: Yes, we offer full OEM, ODM and private label solutions for automotive brands, importers and parts retail chains. Customization covers every level of the product and packaging:
Product marking: Laser-engraved or stamped brand logos, custom part numbers, and tailored heat range / resistance value / electrode specifications
Packaging design: Custom-printed retail boxes, blister cards, inner cartons and master export cartons with your brand artwork and information
ODM development: Custom electrode formulations, structural designs and performance tuning for specialized vehicle or industrial applicationsOur in-house engineering and design team supports the full project cycle from prototype sampling to mass production, helping you build a branded product line aligned with your market positioning.
Q: What is your minimum order quantity?
A: Our standard MOQ varies by order type to fit different business scales:
Stock standard models: 1,000 pcs per SKU, with mixed SKU consolidation supported for bulk shipments
Custom OEM / private label orders: 5,000 pcs per SKU, with flexible adjustment based on customization complexityWe accept small trial orders for new customers to verify product quality and test local market demand, with negotiable minimums for initial cooperation. For long-term partners, we also offer dynamic MOQ adjustment to support lean inventory planning.
Q: How do I find the correct spark plug model for my application?
A: Our technical team maintains a comprehensive cross-reference database covering over 95% of global gasoline engine applications, including passenger cars, light commercial vehicles, motorcycles and small power equipment. You can provide any of the following information for fast, accurate matching:
Original equipment (OE) factory part number
Equivalent competitor brand part number
Full vehicle details: brand, model, model year, engine code and displacement.Our team will verify fitment, heat range compatibility and specification matching, and reply with the corresponding CORINTH part numbers and detailed spec sheets within 24 working hours. Custom regional fitment catalogs can also be provided for distribution partners upon request.
Q: What is the lead time for bulk orders?
A: Lead time depends on inventory status and customization requirements:
Stock items with standard packaging: 7–10 working days from payment confirmation
Mass production orders (custom specifications, private label packaging): 15–25 working days from order confirmation and artwork approvalFor peak season or large-volume annual orders, we recommend placing bookings 4–6 weeks in advance to secure production capacity. We provide real-time order status updates throughout production and shipping, so you can plan your inventory and sales schedule accurately.
Q: Can I request samples before placing a bulk order?
A: Yes, we offer sample orders for quality evaluation and fitment testing prior to bulk purchase.
Sample policy: Up to 10 pcs of standard stock models are provided free of charge. Custom engraved or special-spec samples require a small sampling fee, which can be fully deducted from your first formal bulk order.
Shipping arrangement: The buyer covers courier shipping costs. We can ship via DHL, FedEx, UPS or your designated freight forwarder.
Sample lead time: 3–5 working days from request confirmation. All samples are drawn directly from regular production batches, so their material, workmanship and performance are 100% consistent with mass production goods.
Q: What is your warranty policy?
A: All CORINTH brand spark plugs are covered by a 12-month / 30,000 km warranty (whichever comes first) against manufacturing defects under proper installation and normal operating conditions.
Coverage scope: Defects in materials, workmanship or manufacturing that cause premature failure, such as internal sealing faults, dimensional non-conformity or raw material defects
Exclusions: Damage caused by improper installation, incorrect heat range selection, engine mechanical faults, fuel system abnormalities, modified engines or abnormal operating conditions
Claim process: Simply provide photos of the failed plugs, production batch number and failure description, and our after-sales team will complete verification within 3–5 working days. Valid claims are resolved via replacement product or account credit, at the customer’s option.
Q: What packaging options are available?
A: We offer both standard export packaging and fully custom branded packaging to suit different sales channels and market requirements:
Standard export packaging: Each plug is sealed in an individual anti-rust blister pack, then packed in neutral inner boxes (4 pcs or 10 pcs per box) and reinforced seaworthy export cartons, with palletization available for full container shipments. This option is ideal for wholesale distribution and workshop supply.
Custom branded packaging: Full custom printed retail boxes, blister cards, hanging packs and multi-language labeling with your brand logo, product specifications and regulatory markings. We can also adjust packing specifications, SKU combinations and carton dimensions to match your warehouse management and retail display needs.
