Enterprise Standards
SK9002A — SIKING's proprietary quality grading system
What Is SK9002A?
SK9002A is SIKING's proprietary enterprise quality standard, first established in 1996 and revised in 2009. It defines a grading system for silicone and rubber parts that gives buyers a clear, standardized way to communicate quality expectations.
Unlike generic pass/fail inspection, SK9002A provides two defined quality grades: Grade A (full conformance, premium tier) and Grade B (minor cosmetic deviations, functionally conformant).
This system originated from practical manufacturing experience — some applications demand aesthetic perfection, while others prioritize function over appearance. SK9002A lets you specify exactly what you need.
The Two-Grade System
Clear specifications for both buyer and supplier. No ambiguity about quality expectations.
Grade A — Full Conformance
Parts meet all dimensional specifications within tolerance, have no visual defects visible under standard inspection conditions, pass all functional tests specified, and represent premium-tier quality for applications where appearance matters.
Use when: Visible components, consumer-facing parts, or applications where aesthetic quality is a specification requirement.
Grade B — Functional Conformance
Parts meet all dimensional specifications within tolerance, may have minor cosmetic deviations not visible in final assembly, pass all functional tests specified, and represent functionally conformant parts at a different price point.
Use when: Internal components, hidden parts, or applications where function matters more than appearance.
Using SK9002A in Your Specifications
How to specify exactly what you need in purchasing documents and incoming inspection criteria.
In Purchase Orders
Specify "Grade A only" or "Grade B acceptable" directly in your purchase order. This removes ambiguity about what you're paying for. Grade A parts command a premium because they require stricter process control and higher scrap rates. Grade B parts offer cost savings for applications where minor cosmetics don't matter.
In Incoming Inspection
Your incoming inspection criteria can reference SK9002A grades. If you specified Grade A, your inspectors know exactly what to check for: full dimensional conformance plus visual perfection. This standardizes the conversation between your purchasing and quality teams.
When Grade B Makes Sense
Internal gaskets, hidden seals, protective boots, thermal pads behind covers, and any part not visible to end users. The part functions identically — it just doesn't need to look perfect. Grade B can reduce your total cost significantly for these applications.
SK9002A vs ISO 9001
ISO 9001 is our foundational quality management system — it certifies that we have documented processes and follow them consistently. SK9002A builds on top of that foundation with product-specific grading criteria.
- ISO 9001 certifies our quality management system exists and is followed
- SK9002A defines specific acceptance criteria for silicone and rubber parts
- Together they provide both system certification and product standards
SK9002A is stricter in some areas — enterprise-specific controls for cosmetic grading, dimensional tolerances based on 36 years of manufacturing data, and clear definitions that remove ambiguity from "good enough."
Want to Specify SK9002A Grades in Your Order?
Talk to our quality team about how SK9002A grading works for your specific parts and application requirements.