Just added our new custom made Bimini to our BR175.
nice little up grade and it works well.
IT was made by "Flatwater Covers". He did and excellent job and was only $600 AU including the mounting rings.
It has a clamp on each post, the Bimini is bolted to the clamp via a 6mm S/Steel bolt, the Bimini frame is fully welded and has 4 brackets around it one for each post.
The frame is 3mm wall H/D 5000 series alloy tube with sunbrella top.
You can move the Bimini up and down on the posts.