PBT Filament for Heavy Makeup Style False Eyelashes Generally speaking, the thick false eyelashes will be a little bit heavy when you wear them. But the kind of false eyelashes are made of Tai Hing's PBT Brush Filament, which are more lighter than common plastic filament. So it’s very comfortable for us to wear them for a long time. The end part of PBT Eyelash Filament is round, which highly closes to human eyelashes. With excellent characteristics of uniform diameter, high temperature resistance, good resilience and durability, Relis is very suitable for producing thick false eyelashes.