L-Curl eyelashes are specially designed to allow people with very straight natural lashes to add curls to their eyelashes.
Before the invention of L-Curl lashes, anyone with very straight downturned natural lashes had difficulty achieving nice curls, because C-Curl or D-Curl lashes don’t have enough point of contact with straight lashes to form a strong glue bond. The point of L-Curl lashes is that they do provide the surface area for the bond with the natural straight lash, because the main part of the stem of L-Curl lashes is straight. But they then curve upwards, beyond the bonded area, to give the necessary curl.
The same features are also very helpful for opening up hooded or deep-set eyes. The extension lashes are heading straight ahead and not rubbing up against the eyelid at the start, and only lift into a curl beyond the eyelid.