tow bar bike carrier 2001 Duetto

Hi.
Can anyone recommend a 3 bike tow bar mounted bike rack. I have a 2001 Duetto. I have purchased a Maypole rack but it requires a strap to attach to rear of boot lid or hatch back to steady it, and their tech expert tells me it really needs to be used. This is not really possible with the full length doors on a Duetto, so i will be returning it. I don't need a top of the range rack, but would like it to lock to tow bar and preferably have locks to prevent bike theft. I have looked at Buzz racks as a possibility. I would be interested to hear which racks others are using on this model. Thanks

Hi sammy
Welcome to the forum from Bridington,have a look at the Thule range of racks that to fit onto rear tow balls .
Boaby

Thanks Boaby i will look at their range. i have checked with Witter and they dont require an extra strap, but I with check out Thule as well. Cheers