Grey drainage patent

1. Generally speaking, the drawings in the patent specification are all wireframes. You can draw them with 3D software or project them into an isometric box. Do not use grayscale images.

2. Different parts can't have the same name, otherwise the labels are different when explaining, and the technical terms are the same, which is an unrecognizable problem. You can add left, right, up, down, big, small or left to distinguish names. Don't use 1, 2 to distinguish, you can use one or two to distinguish, because labels are usually Arabic numerals, so if you write them together, it will be confusing.