18mm too girly, can I use 20mm?
On a 46mm 255 yes, but you need to have the needles of your own, plus it will move around. On 255s no.
It's 22mm on 255 and 18mm on 255s.
I know but can I use a 20mm band?
What a problem? If you cut out two corners ca 1mm every side and use own needles. Should work :)
You can do that most probably.
Oh so you have 255s.