O-Ring Certificates of Conformance: House CoC and Manufacturer's CoC
What certification comes with your O-Ring order: The O-Ring Store's House Certificate of Conformance on every order, the Manufacturer's CoC for aerospace and mil-spec, PPAP, and how to request each.
Documentation and traceability are not paperwork for its own sake. In regulated work they are part of the product. When a seal has to be provably the right material, the right size, and traceable back to the batch it came from, the certificate that ships with it matters as much as the O-Ring in the bag. This is a plain-English walk through the certification you get from The O-Ring Store, what is included by default, what is available on request, and how to ask for the right level.
For the reference-page version of this topic, see Certificate of Conformance, cure date, and lot traceability. This article is the customer-facing companion: what actually lands in your box.
Every order: our House Certificate of Conformance
By default, every COTS (Commercial off the Shelf) order you receive from us includes a signed Certificate of Conformance (CoC), printed at the top of the packing list. This is our House CoC, and it certifies that the O-Rings shipped conform to the specifications noted in your order, including:
- Material type (the compound, for example Nitrile, FKM / Viton®, or EPDM)
- Size, per the AS568 standard
- Batch ID, so the lot is identifiable
- Cure date, the quarter and year the rubber was vulcanized (see Storage & Shelf Life for why that date matters)
The certificate is digitally signed by our Quality Control team and is part of our ISO 9001:2015 compliant process. The information on it allows complete internal traceability back to the original manufacturer, which is what supports long-term reliability, compliance, and performance in your application. Nothing to request, nothing extra to pay: it is on the packing list of every order.
Aerospace and mil-spec: the Manufacturer’s Certificate of Conformance
If you are ordering military or aerospace-grade O-Rings, we also include the Manufacturer’s Certificate of Conformance from the original supplier, typically Freudenberg or Precix.
These documents go further than the House CoC. They confirm that the products were produced under strict quality management systems and tested to conform with published specifications, and they show the factory name and manufacturing date for an added layer of transparency. On an aircraft drawing that calls out a spec like MS28775 or AS28775, that manufacturer paper is often part of the requirement, not a nicety. See the mil-spec reference for the specifications these cover, and the Freudenberg N888 article for a worked example of an aerospace grade.
We maintain a library of these documents and are happy to provide them on request for qualifying products. If you are quoting or ordering such items, please tell us in advance so we can ensure proper handling through our warehouse and packing processes.
What each certificate covers
| House CoC | Manufacturer’s CoC | |
|---|---|---|
| Included on | Every COTS order, automatically | Aerospace and mil-spec orders, on request |
| Issued by | The O-Ring Store QC team | The original manufacturer (Freudenberg, Precix) |
| Certifies | Material, AS568 size, batch ID, cure date | Production under the maker’s QMS, tested to published spec |
| Also shows | Internal traceability to the manufacturer | Factory name and manufacturing date |
| Signed | Digitally, by our QC team | By the manufacturer |
| Cost | Included | Included for qualifying products, ask in advance |
PPAP and additional compliance documentation
If your order requires a Production Part Approval Process (PPAP) or additional compliance documentation, we can coordinate that as well. Please note that these requests do incur additional lead time, cost, and setup, depending on the manufacturer’s requirements. The sooner you tell us, the smoother it goes, so include the requirement when you quote rather than after the order is placed.
How to get the right certification with your order
It comes down to one habit: tell us the level of certification you need when you quote or order.
- Standard commercial order? You already have it. The House CoC is on the packing list.
- Aerospace or mil-spec? Ask for the Manufacturer’s CoC up front so we pull it and handle the packing accordingly.
- PPAP or special compliance? Flag it at the quote stage so we can price the lead time and setup.
Send us your requirement with the compound, the size or dash number, and the certification level, and we will make sure it is included or quoted accordingly.
Frequently asked questions
Does every O-Ring order include a Certificate of Conformance?
Yes. Every COTS (Commercial off the Shelf) order includes our signed House Certificate of Conformance at the top of the packing list, at no extra cost. It certifies the material, the AS568 size, the batch ID, and the cure date, and it is part of our ISO 9001:2015 process.
What information is on the House Certificate of Conformance?
Material type (the compound), size per AS568, batch ID, and cure date, digitally signed by our Quality Control team. That information supports full internal traceability back to the original manufacturer.
What is a Manufacturer’s Certificate of Conformance?
It is the certificate from the original manufacturer, typically Freudenberg or Precix, confirming the O-Rings were produced under the maker’s quality management system and tested to published specifications. It also shows the factory name and manufacturing date. We include it for aerospace and mil-spec orders on request.
Do you provide PPAP documentation?
Yes. We can coordinate a Production Part Approval Process or additional compliance documentation. These requests add lead time, cost, and setup depending on the manufacturer’s requirements, so flag them at the quote stage.
Is The O-Ring Store ISO 9001 certified?
Yes. The O-Ring Store operates an ISO 9001:2015 certified quality management system, which is what makes consistent Certificates of Conformance, cure-date reporting, and lot traceability possible.
Certified quality, backed by paperwork
We are here to make getting O-Rings easy, and certified. Every order carries our House Certificate of Conformance, aerospace and mil-spec orders can carry the Manufacturer’s CoC on request, and PPAP and special compliance can be coordinated when you need it. Tell us the level of certification your application requires and we will make sure it is included or quoted.
The O-Ring Store is ISO 9001:2015 certified, audited and certified by LRQA, with a scope that covers the distribution of O-Rings, hydraulic seals, and gaskets, and the assembly of seal kits. You can view our ISO 9001:2015 certificate (PDF) directly: LRQA approval number ISO 9001 00044816, valid through 19 May 2027. That certified quality system is what stands behind every Certificate of Conformance we sign.
See our full Standards & Certifications for FDA, USP Class VI, 3-A, NSF-61, RoHS, REACH, and the mil-spec family.