These needle threaders are my FAVORITES because 1. they work! 2. They are the closest thing to a "forever" threader I've found.
These are made with a single piece of metal so there are no pieces to break. There are two sizes, Classic and Micro.
Micro: For needles size 12 and larger. Use with fine threads (i.e. 6-stranded floss, floche, fine perle cotton, silk thread, beading floss)
Classic: For needles size 9 and larger. Use with fine & medium weight threads (i.e. 6-stranded floss, floche, perle cotton, crewel wool)
If you do lots of fine work, only the Micro Threader will work with smaller embroidery and beading needles.