The products

The material the rule takes out of its own test

On this page11

The escalation stage of the test excludes six materials by name All six share a property rather than a chemistry Which is the same drafting move the main test uses And one leaf in this group is essentially that material Elastic is also the one perishable thing in this group Which puts a real requirement on the container and the shelf partly meets it A cool dark jar slows a loss and does not prevent one The travel sewing kit leaf has the same component and the same problem Everything else in this group is stable And the rule gives a reason to think about it that has nothing to do with storage References

Paper, fabric, yarn, fuzz, elastic, string. Six materials excluded from the second cylinder test.

The escalation stage of the test excludes six materials by name

Any components or pieces that come off during the use and abuse testing go into the cylinder one at a time, excluding paper, fabric, yarn, fuzz, elastic, and string.

Every one is flexible, fibrous or both, and none holds a shape that could lodge somewhere. The exclusion is drawn by what the material does and not by what it is.

Which is the same drafting move the main test uses

Without compressing it. A material that gives way under pressure is treated differently from one that does not, in the main test and in the exclusion list, for the same underlying reason.

And one leaf in this group is essentially that material

A hair tie is an elastic core in a fabric sleeve. Both of its components are on the excluded list, which is a coincidence worth noticing because it describes the article precisely.

Elastic is also the one perishable thing in this group

Rubber and spandex lose elasticity with time, heat and light regardless of how they are stored. It is the only leaf here where the contents degrade on their own.

Which puts a real requirement on the container and the shelf partly meets it

Cool and dark slows the loss. Nine of the 88 containers are amber and one is dark amber, which is the part of this shelf that blocks light, and 21 are clear, which is the part that does not.

A cool dark jar slows a loss and does not prevent one

An old elastic can measure correctly, look correct and fail on first use. Nothing about a container changes that and no page here suggests a container will.

The travel sewing kit leaf has the same component and the same problem

A kit usually carries a short length of elastic alongside the thread, and a kit is by definition the thing that sits unopened for years. The knitting and crochet property reaches the same conclusion from a different direction.

Everything else in this group is stable

Metal cufflinks, a plastic lens case, foam earplugs and the hardware in a sewing kit are all indifferent to time in a closed jar. Which makes the elastic the one storage decision in the group that is about the contents rather than about organization.

And the rule gives a reason to think about it that has nothing to do with storage

A federal test method that takes six materials out of its own gauge test, with elastic among them, is making a judgment about how those materials behave. That judgment is about a hazard and not about shelf life, and these pages do not mix the two.

References

16 CFR 1501.4(b): "(1) Place the article, without compressing it, into the cylinder. If the article fits entirely within the cylinder, in any orientation, it fails to comply with the test procedure. (Test any detached components of the article the same way.) (2) If the article does not fit entirely within the cylinder, subject it to the appropriate “use and abuse” tests of 16 CFR 1500.51 and 1500.52 (excluding the bite tests of 1500.51(c) and 1500.52(c)). Any components or pieces (excluding paper, fabric, yarn, fuzz, elastic, and string) which have become detached from the article as a result of the use and abuse testing shall be placed into the cylinder, one at a time. If any such components or pieces fit entirely within the cylinder, in any orientation and without being compressed, the article fails to comply with the test procedure." law.cornell.edu

The Davis Pack Supply catalog, measured 19 October 2026. 88 containers running 5.545 to 354.882 mL with a median of 88.721: 12 at or under 30 mL, 37 at or under 60, 48 at or under 118 and 85 at or under 177. 85 jars, 2 tubes and one bottle. Ten container families, led by PET Single Wall Jar at 41 and Double Wall Round Base Jar at 16. Nine colors, led by 25 white and 21 clear, then 15 black, 9 amber and 8 natural. Height 0.50 to 5.33 inches with a median of 1.79, recorded for 84 of 88; diameter 0.62 to 3.70 inches with a median of 2.34, recorded for 82. Case packs run 84 to 2,500. Availability, a snapshot and not a promise: 53 of 88 marked available, 34 not, one unrecorded. The fit table records 3,351 on-shelf pairs covering 81 of the 88 containers, and the counts arrive in spikes: 30 containers at 36 fits, 25 at 62, 11 at 17, 7 at 26, 5 at 67, 2 at 8 and one at 1. These are outside dimensions.

Written from 16 CFR part 1501 and from the catalog as it stood on 19 October 2026. That part provides the test method for identifying toys and other articles intended for use by children under three that present a choking, aspiration or ingestion hazard because of small parts; it does not govern contact lens cases, cufflink boxes, earplug carriers, hair ties or travel kits, and it does not reach any container on this shelf. Nothing here determines whether any article is intended for use by children under three, performs or reports any test, or offers guidance about child safety. A closure recorded as fitting a container shares a neck notation in the supplier record, which is not a test of fit.