This page exists so that any number on this site can be traced, questioned and, if it is wrong, corrected.
The source hierarchy
We use sources in this order, and prefer the highest available:
| Tier | Source type | Example |
|---|---|---|
| 1 | Published standards | IEC 60529 for IP codes, ASTM sheet steel specifications, ANSI/BHMA lock grades |
| 2 | Manufacturer specification and installation literature | Published dimensions, load ratings, fastener torque and mounting instructions |
| 3 | Government and institutional data | NIOSH ergonomics guidance, FBI and NICB theft data, code references |
| 4 | Major retailer specification tables | Used only for dimensions and price bands, and flagged as such |
| 5 | First-principles derivation | Geometry, statics, unit conversion, arithmetic shown in full |
We do not treat forum posts, video reviews or retailer marketing copy as sources of fact, though they are useful for identifying which questions people actually have.
What "verified" means in our data
Our modular box specification database marks each row as verified or unverified. Verified means a manufacturer or major retailer specification page for that exact model was retrieved and the figures came from it. Unverified rows are included only where the value is directionally useful and are labelled so you can discount them.
Fields we cannot confirm are left empty rather than estimated. An empty cell is information. A guessed cell is not.
Prices
Prices in tool storage move constantly, vary by region, and are heavily promotional. We therefore publish bands with a date, never single figures, and never treat a price as a specification. A band tells you what tier a product sits in, which is the only thing a price is reliable for over a publication's lifetime.
Derating and analysis conventions
Several guides apply derating factors to published ratings, most visibly in the drawer load calculator. These are engineering planning factors chosen by us, not manufacturer specifications, and they are always printed with the result. They follow three rules:
- Stated, not hidden. The factor and the reason appear next to the output.
- Conservative in the direction that costs nothing. Under-loading a drawer has no failure mode.
- Traceable to a mechanism. Every factor names the physical effect it accounts for, such
as shock loading from rolling over a threshold, or bearing wear in a used slide.
Unit conventions
US customary units first with metric in parentheses on first significant use. Weights in pounds, dimensions in inches, volumes in liters where volume is being compared across products, because liters is the only volume unit manufacturers publish with any consistency.
Sheet steel gauge always refers to the Manufacturers Standard Gauge for sheet steel unless stated otherwise, and we flag where a gauge figure has been carried across from a different material's table, which is a common error.
What we will not do
We also will not publish a ranked "best of" list whose ordering cannot be derived from stated criteria. Comparisons on this site name the criteria first, then apply them, so you can reject our weighting and still use our data.
Checking our work
Every calculator prints its formula. Every derating factor prints its value and its reason. Every article carries its sources. If a figure on this site does not let you check it, that is a defect, and reporting it is genuinely useful.