unsilence air filter

[crazy 340]

need to know what was the correct wing nut for it

I bought and repaint it during the summer now it is ready
to be install but nut sure wich wing nut to use
I know its suppose to be 1/4 wing nut
but dont know what it is suppose to look like

thanks Bob

ps. it s the one that came with 1971 duster 340