The Flat Top Adapter provides a longer throw with 2.00" focusers, which may be necessary with certain eyepiece/telescope combinations to avoid interferences or provide accurate focus.
Tele Vue's adapters use a brass clamping ring to fully encircle the device you're attaching, as opposed to other's efforts which just use a set screw.
Fits all my Televue eyepieces perfectly. Superb quality. It will replace other adapters that provide a poor fit for some of my eyepieces. The large thumbscrew is a joy to use. Could not be happier.
I was looking for something with quality and this one is it. The price was a little high in my opinion but you get what you pay for. Very satisfied.