Halo extensions will not slip or fall out of your hair if applied correctly. This is why additional extra clips are included on either side of the weft for added security if needed. After you apply the Halo, the weight of your hair laying on top will also help keep it in place. 

Ideally, halo hair extensions do not exactly just “sit” on your head. The wire actually wraps itself around the wedged area of your head, near the top of your nape. This area holds the occipital bone, which provides enough wedge for the wire to hold itself in place.

Additionally, 

You can use the additional clips provided with your halo extensions to secure them further. This is not necessary but it is recommended. 

Temporary long time installation

For those planning to keep halo extensions for an additional extended period of time, they can stitch the edges of the wefts together with the natural hair. This way, you will not only keep the hair on your head secured for a longer time, but you will also have the flexibility to style it as you want. 

if the end is stitched, then it makes low ponytail styling easier.