Yes they are Gator style mulching blades
They work very well on vented decks ( holes around the spindle mounts ) but not so good with fabricated decks
Every aftermarket mower parts company makes blades for your mower.
I suggest you buy a set of each type from each supplier and try all of them to find which works best for your mower & grass.
The ones that are not particularly good can be sold on evilpay or craigs list or face ache .
Because those blades recut the clippings into smaller bits they do not have the momentum to throw out of the deck, in fact they are designed not to throw very far
The plain notched blades , both high lift & low lift will throw the clippings out further and be less likely to build up under the deck.
All of the aftermarket suppliers list their blades by length, width, thickness, & mounting hole.
Any blade the same size can be used regardless of what they are officially designed for.
One of my customers runs a fleet of Z Masters using Great Dane blades .
Thicker ( heavier ) blades work best on tall grass and thinner blades leave a finner cut with thin grass.
Then there is Autumn leaves .
More than one customer has several sets of blades to use at different times of the year,
Down here we get very lush wet grass in spring that burns off in summer then the stringy winter grasses take over.
Each requires a different blade to give a professional quality cut .
In any case any of the notched blades should end your build up problem
This is the
Stens Chart
You will have to look up your mower in the catelogues by make & model to find out the actual lengths of your blades .
Blade length is measured like TV's as the diaognal length cutting tip to cutting tip