I replaced the o-ring of my Mule with a GITD one, which is a little thicker and I found the Mule easier to do than the Haiku or especially the 27 models, which are a PITA, I didn't suceed in getting them in totally right and will need new ones (perhaps I can get some spares with the Makai 2x123...)
The only problem on the Mule is, that the GITD doesn't stay exactly round, where the holes are to the outside it gets in a little deeper, which makes it look like a "corner". No big deal, GID is nice, I just need some white trits around the tail now... :devil: