Here's my dirty dozen observing box.
The ones marked with a green dot are Celestron Ultima.
These are a Masuyama design and seem to work excellent in every telescope, short, fat
fast, slow, refractor, reflector, etc.
They were also sold by Orion as the 'Ultrascopic' and Parks 'Gold line' I have since updated
my kit to include a Meade Research Grade 16.8mm my all round favorite.