I received a TB-20 tripod base from Markins today for a Gitzo GT2330 tripod. I emailed Markins before ordering to make sure it was compatible as the tripod is a fairly new model, they said yes. I've tried to fit the base but with no joy, it seems slightly too small and the threads look to be different sizes anyway. I've emailed Markins and told them the same, hopefully they'll get back to me soon. I was just wondering if anyone out there had tried the same combo and if so what was the outcome?? Does it really not fit or am I just living up to my screen name!!? Thanks in advance.