I'm pretty sure they fit Celestion neo's as standard, but I found them a little light-weight for my taste, and had ferrite Celestions fitted instead. They are heavier, but that should not be an issue with a 112 cab. They cost a bit more, but if you are having something made for you, you may as well consider the options, after all there might only be something like £20 in it. They also fit Eminence if requested, and they are more pricey. Ask them to explain the difference between neo and ferrite, the best choice depends on what you play, and your style of playing.
[url="http://professional.celestion.com/bass/index.asp"]http://professional.celestion.com/bass/index.asp[/url]