They almost look like small white golf tees. They have something to do with constructing a cake, I guess, but I have no idea what thier purpose is or how to use them.
They stick into the bottom of the plastic plates and you insert them into the tier below if you use a plastic plate as a separator on a stacked tier. If you look on the bottom of the plastic plates, you'll see some little holes where they go.
How are they different than SPS?
I don't think they go through the cake and sit on the plate below, they're just little pegs that supposedly anchor the cake in place. They're kind of old-school.