What it does
Munach Legarmeih is visually a Munach (the usual conjunctive) followed by a vertical bar called Paseq (׀). The bar transforms the Munach into a disjunctive, it stops the flow that Munach would normally continue. Despite the deceptive shape, this is a pause, not a servant.
Where it appears
Less common. Most often seen in verses with complex internal structure, including the priestly blessing (Birkat Kohanim), where Munach Legarmeih separates the three blessings.
How to remember it
Legarmeih means "by itself" or "on its own." The Munach + Paseq together stand alone, separated from the words that follow. The vertical Paseq bar is the visual cue: when you see Munach followed by a vertical line, it's a disjunctive.
Example from the Torah
Bamidbar 6:25
In the priestly blessing (Bamidbar 6:25), Munach Legarmeih on יְהֹוָ֧ה ׀ separates each invocation of Hashem's name, giving each blessing its own weight.
Hear the melody
A synthesized rendering of the melodic shape, not a vocal recording. For a baal koreh's voice on a full aliyah, PocketTorah is a great free resource.
Hand signal (simanim)
Often confused with
A plain Munach with no Paseq is the standard conjunctive (leads forward). Munach + Paseq (the vertical bar) is Munach Legarmeih, which pauses.