Wool dryer spray
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What it is
A scented spray applied to wool dryer balls so that the scent transfers to the load. A few sprays per wash, so a small bottle lasts a long time and sells at a high price per millilitre.
The archetype it borrows
A topical application type, 10 to 120 mL, narrow neck, HDPE PET or glass, with a dropper, a fine mist sprayer or a plain closure. It is borrowed from a different craft and the window fits, which is why it is here.
The dropper is not the answer
The archetype permits one because of where it came from. A dryer spray is sprayed, and the shelf carries 34 fine mist sprayers. The 43 dropper assemblies on this shelf are an artifact of the borrowing rather than a recommendation.
Essential oil attacks plastic
If the scent is carried in essential oil rather than a water-based fragrance, the bottle and the sprayer both have to tolerate it. Glass is the conservative answer and the shelf carries 59 glass Boston rounds.
The label is the real constraint
At 60 mL there is very little panel. A complete ingredient list, a toll-free number and a website address at a legible size is most of what is available, which is an argument for the label option that permits a shorter list and points at the site.
It is still a designated product
Small does not mean exempt. An air care or general cleaning product used for domestic purposes is inside the definition whatever size the bottle is.
And it is a good second product
It shares a fragrance supplier with a scent booster, it shares a customer with every other laundry product, and it costs very little to add once the disclosure infrastructure exists.