What the shelf brings
On this page9
The closures
230 continuous thread, 43 dropper assemblies, 34 fine mist sprayers, 31 lotion pumps, 19 trigger sprayers, 14 treatment pumps, 14 phenolic and 9 dome lids.
Read that list against the products
Droppers, fine mist sprayers, lotion pumps and treatment pumps are the small half: stain treatment and dryer spray. Nothing in that list is a gallon jug closure except the continuous thread caps.
Which is honest rather than ideal
A spouted closure is what the pour archetype asks for, and the laundry shelf does not bring a dedicated one. A continuous thread cap on an F-style jug is the working answer and it is what most of the category actually uses.
The necks
24-410 at 277, 38-400 at 146, 20-410 at 124, 20-400 at 72, 28-410 at 66, 45-400 at 62. The first three are small-format finishes; 38-400 and 45-400 are where the larger containers live.
Child resistant options follow the neck
As everywhere, a child resistant closure exists for some finishes and not others. If the alkali calculation says you need one, that constrains the neck before it constrains the bottle.
The dropper assemblies are an artifact
They arrive through the archetype carrying wool dryer spray, which is borrowed from a topical application type that permits a dropper. A dryer spray wants a fine mist sprayer, and there are 34 of those on the same shelf.
Shop the closure before the container
In this category the closure is the part with the shorter list, especially at the bulk end. Picking it first and then taking the containers that carry its neck is the order that does not dead-end.
Why the imbalance is not a flaw in the shelf
It reflects the catalog, and the catalog reflects a supplier whose business is small and mid-sized rigid packaging. The bulk laundry trade buys drums and totes from a different kind of supplier entirely. Knowing where the depth stops is more useful than wishing it were elsewhere.