What is 'Catch hook and thin-wall' of plastic mold products?

What is 'Catch hook and thin-wall' of plastic mold products?​

1. The Catch hook

The catch surface and the amount of catch hook are the important basis for the test data during assembe. 
Once made any tiny mistake about these numbers, It would become a huge mistake of the product.

Therefore, during mould design, We needs to pay special attentin to the catch hook assembly and testing.

2. The thin-wall
What is the big problem about thin wall?
The binding point is particularly easy to press and brittle, Then could't pass the test.
It will be difficult to assemble in the next step,
The product will be uneven filling, shrink, and easy broken.