What goes wrong

The plastic was assumed to be fine

On this page14

A plastic jar was bought for tumbler springs Which is static rather than a defect Polypropylene is the worse of the two And glass does not do it A clear plastic jar was bought for key blanks Which removes the reason the jar was clear The oil was not accounted for So the sorted set lost its labels Brass swarf was poured in with the parts One container was used for several sizes Which the shelf has A narrow neck was chosen Glass, small, wide, labelled on the lid References

195 of 251 containers hold a charge.

A plastic jar was bought for tumbler springs

And the springs cling to the inside wall above the heap, where tipping the jar does not move them.

Which is static rather than a defect

A polypropylene or PET wall takes a surface charge from handling, and a few millimetres of steel wire is light enough to be held by it.

Polypropylene is the worse of the two

78 containers against 117 PET. A polyolefin holds a charge more readily.

And glass does not do it

56 of the 251 containers, which is the clean answer and a fifth of the shelf.

A clear plastic jar was bought for key blanks

And hazed, because steel is harder than the wall and shaking marks it. 91 of the 251 containers are clear.

Which removes the reason the jar was clear

A hazed container is not one you can see into, and for a sorted set that was half the value.

The oil was not accounted for

Lock parts arrive lightly oiled, oil defeats an adhesive label, and we publish no marking or labelling service.

So the sorted set lost its labels

Which on a set of ten pin lengths is the whole failure, because the label is the only thing distinguishing them.

Brass swarf was poured in with the parts

Debris from a cut blank is abrasive and scores the jar and the parts together, accelerating both failures.

One container was used for several sizes

A pin of the wrong length is scrap. One size per container is the only workable arrangement and it needs the small end.

Which the shelf has

60 containers under 60 mL and 22 under 30, with 29 at 59 mL alone.

A narrow neck was chosen

And a pin is picked out rather than poured. 112 of the 251 containers are on the two widest common finishes.

Glass, small, wide, labelled on the lid

Which is the recommendation, and the breakage risk is the price of it.

References

The Davis Pack Supply catalog, measured 19 October 2026. The 251 containers on this shelf are 117 PET, 78 polypropylene and 56 glass, so 195 plastic against 56 glass, a little over four to one. For a small metal part the difference is practical: glass does not scratch, does not haze and does not take a static charge, and both plastics do all three.

The Davis Pack Supply catalog, measured 19 October 2026. 539 rows: 251 containers and 288 closures. This is the store-small-dry shelf, shared identically by nine groups, and the sewing notions property enumerates the inventory. 5 to 500 mL with a median of 177, with 60 containers under 60 mL and 22 under 30. 210 jars, 27 bottles, 12 tubs and pails, 2 tubes. Buyability, a snapshot: 159 of 251 available, 91 not, 1 unrecorded; 93 quote only; 65 full case only, with case packs from 12 to 6,370 and a median of 288.

Written from 18 U.S.C. 1704 and from the catalog as it stood on 19 October 2026. That section is a theft and forgery statute about keys to Postal Service locks and says nothing about containers, labeling or packaging; it is quoted because it is the federal provision that names a key. Nothing here addresses the lawfulness of making, holding or selling any key or key blank, locksmith licensing, restricted keyways, key duplication, or whether any mark has legal effect, and nothing here would assist anybody in defeating a lock. This shelf is shared identically by nine groups and the sewing notions property enumerates the inventory.