Shift Knob Ford Mustang 2005

I want to buy my boyfriend a dragon ball Z shift knob for his 2005 Ford mustang Gt for his Birthday. Although I don't know anything about cars! I don't know what diameter or thread size to get! Guys Please help!

https://www.etsy.com/listing/187545578/dragonball-z-shift-knob

or how can I figure this out without directly asking him or making it very obvious? Any ideas?

Added (1). Btw his car is Manual Transmission

They are made to order, so it will have whatever threads you want. You need 12mm with a 1.75 thread pitch

I had a look at the link, the ad says send them a note if you don't know about thread sizes and what car it is going on.

If he has a manual transmission, you're okay. If it's an automatic, then probably not…

This should fit any car