Questions about robot materials choosing

It says that we must use VEX official materials to build our robots, but can I use materials from play field on my robot? Is that illegal?

What exactly do you mean by materials from play field?

I’ve bolded some specific text from the game manual below.

Hope this helps

I mean if I use the nuts or something else which are initially used to build play field.

Thanks a lot!!! It DOES really help.

See Rue R7 c. below. It lists which sizes of screws and nuts are allowed, aside from the VEX 8-32 screws.