What is a syphon jet flush toilet?

What is a syphon jet flush toilet? I am putting in a new toilet on the fourth floor of my house and the water pressure is not that great. Does a syphon jet flush toilet need alot of pressure or is it like a regular toilet that is a gravity fed toilet?

A siphon jet bowl has a jet at the front that water comes from, and it starts the siphon.

Old style bowls only wash down from the upper rim holes.

So I don't have to worry about having strong water pressure? Its not like a public restroon toilet?

So I don't have to worry about having strong water pressure? Its not like a public restroom toilet?

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Most toilets for home use have a tank combined with the siphon jet.
It can either be a gravity tank, which works with any pressure over 20 PSI
or a pressure assist, they would need more pressure to work well.

Commercial valves rely on large pipes to each toilet.
You will never be able to use those in a home successfully without adding a storage tank behind the wall.

If you're buying a toilet with a tank, then the 20 PSI is all you need.
With the siphon flush, some water comes from the small hole on the near side of the bowl, and the rest comes from the rim as it rinses down the bowl.