Affordable and useful.
These fit the scentbird bottles perfectly so I don't have to re bottle to use them.  The quality isnt quite as nice as the scentbird, but those are $15 for extra ones and these are perfectly serviceable for much less.  The fact that these come with the empty glass inner bottles too will come in handy to carry other liquids for traveling, or if I want a travel size of another fragrance that I already own.
Rating: 4 stars