What cage is good for the yellow waist willow warrior?

The yellow waist willow warbler usually uses a cage with a silk spacing of 0.8-1.1. Of course, below 1.0 is more secure, which can avoid it.The bird's body is very small, with a length of about 8-11 cm. The upper body is olive-green, with yellow-green longitudinal patterns in the middle of the head and white abdomen.It is usually moved in the branches and leaves on the top of the tree. You can jump around to find food, usually in insects as food.