Like so many, you've been suckered into the "Alibaba experience". That's not glass... and you'll note that nowhere, other than in the usual - everything but the kitchen sink" title, do they mention actual glass. I've seen a few that do... and they're simply lying.
The Kayfun design is held together as an assembly with a threaded external body. With few, rare and costly exceptions, can you apply a fine thread to glass... so you won't be finding it in attys, not even genuine, $150 ones.
There are glass conversion kits for the Kayfun, Russian and 1:1 clones, but they are essentially a carto tank affair where the end caps thread onto the base and top cap of the Kayfun et al, and the glass - and for that matter the entire atty - is held together with tightly fitting o-rings.
"
Science of Vaping" conversion with o-rings removed.