Explain flexydually

I find myself wanting for a little more detail on the print head pages on the lulzbot website (https://www.lulzbot.com/store/tool-heads/lulzbot-taz-flexydually-tool-head-v2). I would like to know what exactly is the flexy dually. How does it differ from the dually? Does it have one flexy head and one normal head? Does it have two flexy heads?

While I’m on the subject, it would be nice to know exactly how the flexy head is different from the normal head. What makes it better for flexy material?

Thanks

Here is a picture of both dual extruders from above. The one on the left is the flexydually. You can see the top extruder is different, having a green block and small hole with a tube instead of an idler arm on a spring. This makes a tighter path up to and over the hobbed bolt so the filament can’t bend. (The rear extruder is for “normal” filament and the front is for flexible.)

Otherwise, they are pretty much identical except that the flexydually has 0.6mm nozzles and the “regular” dual extruder has 0.5mm nozzles.

Hope that covers it.