THE MATERIALS
Not all stainless steel is the same.
Why Grades Matter
"Stainless steel" is a category, not a single material. There are over 150 grades, each with different compositions and properties. For food containers, the grade determines:
- How well it resists corrosion
- Whether it reacts with your food
- How long it lasts
- Whether it's safe for cooking vs. just storage
If a product just says "stainless steel" without specifying the grade, that's not transparency — that's vagueness.
Four grades you'll encounter.
Grade 201 — The Budget Option
| Composition | 16-18% Cr, 3.5-5.5% Ni, 5.5-7.5% Mn |
| Corrosion resistance | Low |
| Food safe | Technically yes, but lower corrosion resistance means higher metal release over time |
| Our view | Not suitable for food storage that will be heated or used long-term |
Grade 304 (18/8) — The Food-Grade Standard ← What we use
| Composition | 18% Cr, 8% Ni |
| Corrosion resistance | High |
| Food safe | Yes — the benchmark for food contact materials worldwide |
| Common in | Hospital equipment, commercial kitchens, high-quality cookware |
| Our view | The right grade for food storage. Proven, tested, well-understood |
Grade 316 — The Surgical/Marine Grade
| Composition | 16% Cr, 10% Ni, 2% Mo (molybdenum) |
| Corrosion resistance | Very high (resists chlorides) |
| Our view | Superior corrosion resistance, but overkill for food storage. Added cost without meaningful kitchen benefit |
Grade 430 — The Ferritic Option
| Composition | 16-18% Cr, <0.75% Ni |
| Corrosion resistance | Moderate |
| Our view | Fine for appliance surfaces, not ideal for repeated food contact |
How to verify what you're buying.
- Look for grade markings. Reputable manufacturers stamp the grade on the product. Our containers are stamped SS304. Be aware that an imprint or simple laser engraving of SS304 or SUS304 is easy to add to any steel — verify against the price, because low-cost containers often use a lower grade of stainless steel.
- Ask for a mill certificate. This traces the steel back to the mill that produced it.
- Independent composition testing. A chemical composition analysis reads the exact elements in the steel. We commission ours independently and publish the composition figures in our product specification, with the full lab report available on request.
What to watch for:
- "Stainless steel" with no grade specified — could be any grade
- "Food grade stainless steel" — marketing term, not a grade specification
- "18/10" — this is 316 or similar. Nothing wrong with it, but check the price