What is plad? It's mentioned in a parody video in YouTube?

Ok so it's mentioned in the tik Tok parody by that Josh guy on YouTube (the same one who did Tuesday, Friday parody) and he says this bit 'my car spelt bad, so I wore some plad, I got myself an airfreshener, it's called peachy peach but it smells like an elf...' anyways I've heard it in heaps of songs. What the hell is plad????