That depends on your enclosure, how much of it you're trying to mist, and nozzle placement. I bought the v5.0 starter system w/ no extras. It comes with one nozzle, but no mounting bracket. I have a double-size (48"W) enclosure, so I asked both MistKing and the enclosure mfr. how many nozzles I would need. They both told me 4, and where to put them.
After doing some testing and trial runs with the single nozzle, I found that I could sufficiently mist my enclosure with just 3 nozzles, so I did, and it's working fine. That only saved $15, but paraphrasing the old joke, $15 is $15.
With a 24 x 24 x 48 enclosure, you
may be able to do with the one nozzle if placed top center aiming downward. Supporting it there might be tricky, and may negate the savings of a second nozzle.
It also depends on the enclosure you have/buy and if it comes with mister nozzle mounting brackets—some do and some don't. The MistKing starter system does not come with any mounting bracket, and you will need one bracket for every nozzle.
So unless you already have some brackets, you'll need one for every nozzle. Hope that's clear.
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