The clamps we used are originally for high tech medical equipment. High quality stainless steel, and very sturdy. Since the Outbound have two very robust poles aft, it makes the Bimini-installation less "messy" by using these instead of separate tubing aft. These clamps exist in different sizes, so not only for this purpose.
They are Behringer clamps (https://www.austenitex.com/). We saw these on their SV Kinetic and loved them. Have several on Horizon today.
Here is a link to where we bought ours.
https://www.austenitex.com/behringer-cht-series-compact-hygienic-threaded-mount-hangers?size=306&hardware-material=2&insert-material=1
Make sure to choose the 316 stainless steel variant.
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