Hakuhodo G5533 and G5523 are eye shadow brushes made of blue squirrel hair. I love Hakuhodo's G series because it offers many interesting shapes and a variety of hair types. These two are pretty basic as far as eye shadow brushes go, but they're worth attention because of the hair quality.
Hakuhodo G5533 is a blending brush. It's shaped like a narrow whisk and is very fluffy. So much so, actually, that it took me a while to learn how to make the best use of this brush. Blue squirrel is extremely soft, so if you've never blended your eye shadow with anything other than MAC 217 you're likely to question the effectiveness of Hakuhodo G5533. It's not just soft and fluffy but also not very dense. This means that the brush will not grab or move a lot of product, so it's great when you need to be careful not to mess up your color placement. The brush is wonderfully soft and gentle and will delight those with sensitive skin who have issues with goat hair.
Hakuhodo G5523 is a flat paddle-shaped eye shadow brush that works well for creating a soft wash or for a very gentle placing of a bold color on the lid and lightly blending it into the base. Using G5523 is pretty intuitive. It's a hard working brush for me both because of the practical shape and the pleasant way it feels.
Bottom Line: while G5533 is in the "nice to have" extra brush category, G5523 is a staple.
Hakuhodo G5533 ($24) and G5523 ($26) Eye Shadow Brushes are available from HakuhodoUSA.com. They ship all over the world.