Flat lashes are better because they provide:
Increased eyeliner effect
Amplified texture
Improved retention because the contact area for the adhesive is larger
More volume without the extra weight
Elevated drama
Ability to use less adhesive
 
Flat lashes, also known as ellipse or cashmere lashes, are eyelash extensions with an oval, rather than round, base and a split tip. This design makes them lighter, gives them a softer, more flexible feel, and creates a wider surface area for better adhesion to the natural lash, resulting in improved retention. They offer a more dramatic, darker look similar to a classic set but without the added weight, making them a good option for clients with weaker or sparser natural lashes.