This tube clamp solidly holds a sub plate and on top of that a Bowducer baseplate. 3 cap head screws allow it to be very solidly attached to a tube railing.
The clamp is aluminum with socket head cap screws. The clamp itself is very smooth but care should be taken if using a boat cover due to the upper 4x4 inch square sub plate. It is likely best to remove that plate when using a cover that goes over the top of the railing.
Please be sure of the diameter of your tube. The 7/8 clamp does not fit 1 inch tube and the 1 inch clamp will not secure to a 7/8 inch tube.
