Seriously. Plurals do NOT have apostrophes.
A zipper......
As for the UFO's fly, such a fly has no wings, it's kind of circular in shape, and is often silent while flying. Some of them reportedly are triangular in shape, perhaps because that species does have wings, but does no more than extend them withing flapping them.
And some of them are rather elongated in shape, very similar to what we'd call a bumblebee, but these have no wings, since they don't need them, and they couldn't use wings if they had them, because they'd be too heavy if they did have wings, and therefore could not fly.
They are usually carried in clear plastic vials and released randomly around the world, often at night.
As for the UFO's fly, such a fly has no wings, it's kind of circular in shape, and is often silent while flying. Some of them reportedly are triangular in shape, perhaps because that species does have wings, but does no more than extend them without flapping them.
And some of them are rather elongated in shape, very similar to what we'd call a bumblebee, but these have no wings, since they don't need them, and they couldn't use wings if they had them, because they'd be too heavy if they did have wings, and therefore could not fly.
They are usually carried in clear plastic vials and released randomly around the world, often at night.
They are posting about UFO technology conspiracies and you want proper grammar? I think your standards are too high. :-)